The 100 most-cited articles in Angewandte Chemie International Edition, 2023

Abstract We demonstrate the great feasibility of MBenes as a new class of tandem catalysts for electrocatalytic nitrate reduction to ammonia (NO 3 RR). As a proof of concept, FeB 2 is first employed as a model MBene catalyst for the NO 3 RR, showing a maximum NH 3 ‐Faradaic efficiency of 96.8 % with a corresponding NH 3 yield of 25.5 mg h −1 cm −2 at −0.6 V vs. RHE. Mechanistic studies reveal that the exceptional NO 3 RR activity of FeB 2 arises from the tandem catalysis mechanism, that is, B sites activate NO 3 − to form intermediates, while Fe sites dissociate H 2 O and increase *H supply on B sites to promote the intermediate hydrogenation and enhance the NO 3 − ‐to‐NH 3 conversion.

Antimicrobial resistance (AMR) is one of the biggest threats to the environment and health. AMR rapidly invalidates conventional antibiotics, and antimicrobial nanomaterials have been increasingly explored as alternatives. Interestingly, several antimicrobial nanomaterials show AMR-independent antimicrobial effects without detectable new resistance and have therefore been suggested to prevent AMR evolution. In contrast, some are found to trigger the evolution of AMR. Given these seemingly conflicting findings, a timely discussion of the two faces of antimicrobial nanomaterials is urgently needed. This review systematically compares the killing mechanisms and structure-activity relationships of antibiotics and antimicrobial nanomaterials. We then focus on nano-microbe interactions to elucidate the impacts of molecular initiating events on AMR evolution. Finally, we provide an outlook on future antimicrobial nanomaterials and propose design principles for the prevention of AMR evolution.

Abstract Benefiting from the excellent structural tunability, robust framework, ultrahigh porosity, and rich active sites, covalent organic frameworks (COFs) are widely recognized as promising photocatalysts in chemical conversions, and emerged in the hydrogen peroxide (H 2 O 2 ) photosynthesis in 2020. H 2 O 2 , serving as an environmental‐friendly oxidant and a promising liquid fuel, has attracted increasing researchers to explore its potential. Over the past few years, numerous COFs‐based photocatalysts are developed with encouraging achievements in H 2 O 2 production, whereas no comprehensive review articles exist to summarize this specific and significant area. Herein we provide a systematic overview of the advances and challenges of COFs in photocatalytic H 2 O 2 production. We first introduce the priorities of COFs in H 2 O 2 photosynthesis. Then, various strategies to improve COFs photocatalytic efficiency are discussed. The perspective and outlook for future advances of COFs in this emerging field are finally offered. This timely review will pave the way for the development…

Cyclic peptides are fascinating molecules abundantly found in nature and exploited as molecular format for drug development as well as other applications, ranging from research tools to food additives. Advances in peptide technologies made over many years through improved methods for synthesis and drug development have resulted in a steady stream of new drugs, with an average of around one cyclic peptide drug approved per year. Powerful technologies for screening random peptide libraries, and de novo generating ligands, have enabled the development of cyclic peptide drugs independent of naturally derived molecules and now offer virtually unlimited development opportunities. In this review, we feature therapeutically relevant cyclic peptides derived from nature and discuss the unique properties of cyclic peptides, the enormous technological advances in peptide ligand development in recent years, and current challenges and opportunities for developing cyclic peptides that address unmet medical needs.

Abstract Photocatalytic water splitting and carbon dioxide (CO2) reduction provide promising solutions to global energy and environmental issues. In recent years, metal‐organic frameworks (MOFs), a class of crystalline porous solids featuring well‐defined and tailorable structures as well as high surface areas, have captured great interest toward photocatalytic water splitting and CO2 reduction. In this review, the semiconductor‐like behavior of MOFs is first discussed. We then summarize the recent advances in photocatalytic water splitting and CO2 reduction over MOF‐based materials and focus on the unique advantage of MOFs for clarifying the structure‐property relationship in photocatalysis. In addition, some representative characterization techniques have been presented to unveil the photocatalytic kinetics and reaction intermediates in MOF‐based systems. Finally, the challenges, and perspectives for future directions are proposed.

Abstract Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built‐in electric field (BEF) strategy to fabricate heterogeneous nickel phosphide‐cobalt nanowire arrays grown on carbon fiber paper (Ni 2 P‐CoCH/CFP) with large work function difference (ΔΦ) as bifunctional electrocatalysts for overall water splitting. Impressively, Ni 2 P‐CoCH/CFP exhibits a remarkable catalytic activity for hydrogen and oxygen evolution reactions to obtain 10 mA cm −2 , respectively. Moreover, the assembled lab‐scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis with a 100 % faradic efficiency. Computational calculations combining with experiments reveal the interface‐induced electric field effect facilitates asymmetrical charge distributions, thereby regulating the adsorption/desorption of the intermediates during reactions. This work offers an avenue to rationally design high‐performance heterogeneous electrocatalysts.

Two-dimensional (2D) transition metal dichalcogenides (TMDs), a rising star in the post-graphene era, are fundamentally and technologically intriguing for photocatalysis. Their extraordinary electronic, optical, and chemical properties endow them as promising materials for effectively harvesting light and catalyzing the redox reaction in photocatalysis. Here, we present a tutorial-style review of the field of 2D TMDs for photocatalysis to educate researchers (especially the new-comers), which begins with a brief introduction of the fundamentals of 2D TMDs and photocatalysis along with the synthesis of this type of material, then look deeply into the merits of 2D TMDs as co-catalysts and active photocatalysts, followed by an overview of the challenges and corresponding strategies of 2D TMDs for photocatalysis, and finally look ahead this topic.

Abstract Photocatalytic oxygen reduction reaction (ORR) offers a promising hydrogen peroxide (H 2 O 2 ) synthetic strategy, especially the one‐step two‐electron (2e − ) ORR route holds great potential in achieving highly efficient and selectivity. However, efficient one‐step 2e − ORR is rarely harvested and the underlying mechanism for regulating the ORR pathways remains greatly obscure. Here, by loading sulfone units into covalent organic frameworks (FS‐COFs), we present an efficient photocatalyst for H 2 O 2 generation via one‐step 2e − ORR from pure water and air. Under visible light irradiation, FS‐COFs exert a superb H 2 O 2 yield of 3904.2 μmol h −1 g −1 , outperforming most reported metal‐free catalysts under similar conditions. Experimental and theoretical investigation reveals that the sulfone units accelerate the separation of photoinduced electron‐hole (e − ‐h + ) pairs, enhance the protonation of COFs, and promote O 2 adsorption in the Yeager‐type, which jointly alters the reaction process from two‐step 2e − ORR to the one‐step one, thereby achieving efficient H 2 O 2…

Abstract H 2 O 2 is a significant chemical widely utilized in the environmental and industrial fields, with growing global demand. Without sacrificial agents, simultaneous photocatalyzed H 2 O 2 synthesis through the oxygen reduction reaction (ORR) and water oxidation reaction (WOR) dual channels from seawater is green and sustainable but still challenging. Herein, two novel thiophene‐containing covalent organic frameworks (TD‐COF and TT‐COF) were first constructed and served as catalysts for H 2 O 2 synthesis via indirect 2e − ORR and direct 2e − WOR channels. The photocatalytic H 2 O 2 production performance can be regulated by adjusting the N ‐heterocycle modules (pyridine and triazine) in COFs. Notably, with no sacrificial agents, just using air and water as raw materials, TD‐COF exhibited high H 2 O 2 production yields of 4060 μmol h −1 g −1 and 3364 μmol h −1 g −1 in deionized water and natural seawater, respectively. Further computational mechanism studies revealed that the thiophene was the primary photoreduction unit for ORR, while the benzene ring (linked to the thiophene…

Abstract Herein, we successfully construct bifunctional electrocatalysts by synthesizing atomically dispersed Fe−Se atom pairs supported on N‐doped carbon (Fe−Se/NC). The obtained Fe−Se/NC shows a noteworthy bifunctional oxygen catalytic performance with a low potential difference of 0.698 V, far superior to that of reported Fe‐based single‐atom catalysts. The theoretical calculations reveal that p‐d orbital hybridization around the Fe−Se atom pairs leads to remarkably asymmetrical polarized charge distributions. Fe−Se/NC based solid‐state rechargeable Zn‐air batteries (ZABs−Fe−Se/NC) present stable charge/discharge of 200 h (1090 cycles) at 20 mA cm−2 at 25 °C, which is 6.9 times of ZABs−Pt/C+Ir/C. At extremely low temperature of −40 °C, ZABs−Fe−Se/NC displays an ultra‐robust cycling performance of 741 h (4041 cycles) at 1 mA cm−2, which is about 11.7 times of ZABs−Pt/C+Ir/C. More importantly, ZABs−Fe−Se/NC could be operated for 133 h (725 cycles) even at 5 mA cm−2 at −40 °C.

Abstract Artificial H 2 O 2 photosynthesis by covalent organic frameworks (COFs) photocatalysts is promising for wastewater treatment. The effect of linkage chemistry of COFs as functional basis to photoelectrochemical properties and photocatalysis remains a significant challenge. In this study, three kinds of azoles‐linked COFs including thiazole‐linked TZ‐COF, oxazole‐linked OZ‐COF and imidazole‐linked IZ‐COF were successfully synthesized. More accessible channels of charge transfer were constructed in TZ‐COF via the donor‐π‐acceptor structure between thiazole linkage and pyrene linker, leading to efficient suppression of photoexcited charge recombination. Density functional theory calculations support the experimental studies, demonstrating that the thiazole linkage is more favorable for the formation of *O 2 intermediate in H 2 O 2 production than that of the oxazole and imidazole linkages. The real active sites in COFs located at the benzene ring fragment between pyrene unit and azole linkage.

Abstract Intensifying energy crises and severe environmental issues have led to the discovery of renewable energy sources, sustainable energy conversion, and storage technologies. Photocatalysis is a green technology that converts eco‐friendly solar energy into high‐energy chemicals. Covalent organic frameworks (COFs) are porous materials constructed by covalent bonds that show promising potential for converting solar energy into chemicals owing to their pre‐designable structures, high crystallinity, and porosity. Herein, we highlight recent progress in the synthesis of COF‐based photocatalysts and their applications in water splitting, CO 2 reduction, and H 2 O 2 production. The challenges and future opportunities for the rational design of COFs for advanced photocatalysts are discussed. This Review is expected to promote further development of COFs toward photocatalysis.

Abstract Although zeolitic imidazolate framework‐8 (ZIF‐8) has been applied in various tumor therapies, the intrinsic immunogenicity remains unclear. Here, we initiatively discover that ZIF‐8 nanoparticles (NPs) can intrinsically induce pyroptosis by a caspase‐1/gasdermin D (GSDMD)‐dependent pathway. The pyroptotic cell death is accompanied by necrosis and immunogenic cell death (ICD) simultaneously for efficient in situ immunity initiation. Meanwhile, carbonyl cyanide m‐chlorophenyl hydrazone (CCCP), a mitochondrial depolarizing agent, is successfully loaded into ZIF‐8 NPs and found to further enhance the pyroptosis process. Collectively, the obtained Pluronic F127‐modified CCCP‐incorporated ZIF‐8 NPs ( F127 ZIF‐8 CCCP NPs) activate antitumor immunity and reprogram immunosuppressive tumor microenvironment (TME), realizing high‐efficiency tumor growth inhibition. This work will facilitate biomedicine applications of ZIF‐8 and provide good inspiration for pyroptosis‐induced cancer therapy.

Abstract Electrochemical conversion of nitrate (NO 3 − ) into ammonia (NH 3 ) represents a potential way for achieving carbon‐free NH 3 production while balancing the nitrogen cycle. Herein we report a high‐performance Cu nanosheets catalyst which delivers a NH 3 partial current density of 665 mA cm −2 and NH 3 yield rate of 1.41 mmol h −1 cm −2 in a flow cell at −0.59 V vs. reversible hydrogen electrode. The catalyst showed a high stability for 700 h with NH 3 Faradaic efficiency of ≈88 % at 365 mA cm −2 . In situ spectroscopy results verify that Cu nanosheets are in situ derived from the as‐prepared CuO nanosheets under electrochemical NO 3 − reduction reaction conditions. Electrochemical measurements and density functional theory calculations indicate that the high performance is attributed to the tandem interaction of Cu(100) and Cu(111) facets. The NO 2 − generated on the Cu(100) facets is subsequently hydrogenated on the Cu(111) facets, thus the tandem catalysis promotes the crucial hydrogenation of *NO to *NOH for NH 3 production.

Abstract Four highly porous covalent organic frameworks (COFs) containing pyrene units were prepared and explored for photocatalytic H 2 O 2 production. The experimental studies are complemented by density functional theory calculations, proving that the pyrene unit is more active for H 2 O 2 production than the bipyridine and (diarylamino)benzene units reported previously. H 2 O 2 decomposition experiments verified that the distribution of pyrene units over a large surface area of COFs plays an important role in catalytic performance. The Py‐Py‐COF though contains more pyrene units than other COFs which induces a high H 2 O 2 decomposition due to a dense concentration of pyrene in close proximity over a limited surface area. Therefore, a two‐phase reaction system (water‐benzyl alcohol) was employed to inhibit H 2 O 2 decomposition. This is the first report on applying pyrene‐based COFs in a two‐phase system for photocatalytic H 2 O 2 generation.

Since the insight to fuse Fenton chemistry and nanomedicine into cancer therapy, great signs of progress have been made in the field of chemodynamic therapy (CDT). However, the exact mechanism of CDT is obscured by the unique tumor chemical environment and inevitable nanoparticle-cell interactions, thus impeding further development. In this Scientific Perspective, the significance of CDT is clarified, the complex mechanism is deconstructed into primitive chemical and biological interactions, and the mechanism research directions based on the chemical kinetics and biological signaling pathways are discussed in detail. Moreover, beneficial outlooks are presented to enlighten the evolution of next-generation CDT. Hopefully, this Scientific Perspective can inspire new ideas and advances for CDT and provide a reference for breaking down the interdisciplinary barriers in the field of nanomedicine.

Abstract Highly reversible plating/stripping in aqueous electrolytes is one of the critical processes determining the performance of Zn‐ion batteries, but it is severely impeded by the parasitic side reaction and dendrite growth. Herein, a novel electrolyte engineering strategy is first proposed based on the usage of 100 mM xylitol additive, which inhibits hydrogen evolution reaction and accelerates cations migration by expelling active H2O molecules and weakening electrostatic interaction through oriented reconstruction of hydrogen bonds. Concomitantly, xylitol molecules are preferentially adsorbed by Zn surface, which provides a shielding buffer layer to retard the sedimentation and suppress the planar diffusion of Zn2+ ions. Zn2+ transference number and cycling lifespan of Zn∥Zn cells have been significantly elevated, overwhelmingly larger than bare ZnSO4. The cell coupled with a NaV3O8 cathode still behaves much better than the additive‐free device in terms of capacity retention.

Abstract Nitrogen‐heterocycle‐based covalent organic frameworks (COFs) are considered promising candidates for the overall photosynthesis of hydrogen peroxide (H 2 O 2 ). However, the effects of the relative nitrogen locations remain obscured and photocatalytic performances of COFs need to be further improved. Herein, a collection of COFs functionalized by various diazines including pyridazine, pyrimidine, and pyrazine have been judiciously designed and synthesized for photogeneration of H 2 O 2 without sacrificial agents. Compared with pyrimidine and pyrazine, pyridazine embedded in TpDz tends to stabilize endoperoxide intermediate species, leading toward the more efficient direct 2e ‐ oxygen reduction reaction (ORR) pathway. Benefiting from the effective electron‐hole separation, low charge transfer resistance, and high‐efficiency ORR pathway, an excellent production rate of 7327 μmol g −1 h −1 and a solar‐to‐chemical conversion (SCC) value of 0.62 % has been achieved by TpDz, which ranks one of the best COF‐based photocatalysts. This work might shed fresh light on the rational…

Abstract Nickel‐based catalysts have been regarded as one of the most promising electrocatalysts for urea oxidation reaction (UOR), however, their activity is largely limited by the inevitable self‐oxidation reaction of Ni species (NSOR) during the UOR. Here, we proposed an interface chemistry modulation strategy to trigger the occurrence of UOR before the NSOR via constructing a 2D/2D heterostructure that consists of ultrathin NiO anchored Ru−Co dual‐atom support (Ru‐Co DAS/NiO). Operando spectroscopic characterizations confirm this unique triggering mechanism on the surface of Ru‐Co DAS/NiO. Consequently, the fabricated catalyst exhibits outstanding UOR activity with a low potential of 1.288 V at 10 mA cm −2 and remarkable long‐term durability for more than 330 h operation. DFT calculations and spectroscopic characterizations demonstrate that the favorable electronic structure induced by this unique heterointerface endows the catalyst energetically more favorable for the UOR than the NSOR.

Optimizing the electronic structure of covalent organic framework (COF) photocatalysts is essential for maximizing photocatalytic activity. Herein, we report an isoreticular family of multivariate COFs containing chromenoquinoline rings in the COF structure and electron-donating or withdrawing groups in the pores. Intramolecular donor-acceptor (D-A) interactions in the COFs allowed tuning of local charge distributions and charge carrier separation under visible light irradiation, resulting in enhanced photocatalytic performance. By optimizing the optoelectronic properties of the COFs, a photocatalytic uranium extraction efficiency of 8.02 mg/g/day was achieved using a nitro-functionalized multicomponent COF in natural seawater, exceeding the performance of all COFs reported to date. Results demonstrate an effective design strategy towards high-activity COF photocatalysts with intramolecular D-A structures not easily accessible using traditional synthetic approaches.

Abstract The electrochemical conversion of nitrate pollutants into value‐added ammonia is a feasible way to achieve artificial nitrogen cycle. However, the development of electrocatalytic nitrate‐to‐ammonia reduction reaction (NO 3 − RR) has been hampered by high overpotential and low Faradaic efficiency. Here we develop an iron single‐atom catalyst coordinated with nitrogen and phosphorus on hollow carbon polyhedron (denoted as Fe−N/P−C) as a NO 3 − RR electrocatalyst. Owing to the tuning effect of phosphorus atoms on breaking local charge symmetry of the single‐Fe‐atom catalyst, it facilitates the adsorption of nitrate ions and enrichment of some key reaction intermediates during the NO 3 − RR process. The Fe−N/P−C catalyst exhibits 90.3 % ammonia Faradaic efficiency with a yield rate of 17980 μg h −1 mg cat −1 , greatly outperforming the reported Fe‐based catalysts. Furthermore, operando SR‐FTIR spectroscopy measurements reveal the reaction pathway based on key intermediates observed under different applied potentials and reaction durations. Density functional theory calculations…

Understanding the intricate molecular machinery that governs ferroptosis and leveraging this accumulating knowledge could facilitate disease prevention, diagnosis, treatment, and prognosis. Emerging approaches for the in situ detection of the major regulators and biological events across cellular, tissue, and in living subjects provide a multiscale perspective for studying ferroptosis. Furthermore, advanced applications that integrate ferroptosis detection and the latest technologies hold tremendous promise in ferroptosis research. In this review, we first briefly summarize the mechanisms and key regulators underlying ferroptosis. Ferroptosis detection approaches are then presented to delineate their design, mechanisms of action, and applications. Special interest is placed on advanced ferroptosis applications that integrate multifunctional platforms. Finally, we discuss the prospects and challenges of ferroptosis detection approaches and applications, with the aim of providing a roadmap for the theranostic development of a broad range of ferroptosis-related diseases.

Abstract The aqueous electrocatalytic reduction of NO 3 − into NH 3 (NitrRR) presents a sustainable route applicable to NH 3 production and potentially energy storage. However, the NitrRR involves a directly eight‐electron transfer process generally required a large overpotential (<−0.2 V versus reversible hydrogen electrode ( vs . RHE)) to reach optimal efficiency. Here, inspired by biological nitrate respiration, the NitrRR was separated into two stages along a [2+6]‐electron pathway to alleviate the kinetic barrier. The system employed a Cu nanowire catalyst produces NO 2 − and NH 3 with current efficiencies of 91.5 % and 100 %, respectively at lower overpotentials (>+0.1 vs . RHE). The high efficiency for such a reduction process was further explored in a zinc‐nitrate battery. This battery could be specified by a high output voltage of 0.70 V, an average energy density of 566.7 Wh L −1 at 10 mA cm −2 and a power density of 14.1 mW cm −2 , which is well beyond all previously reported similar concepts.

Abstract Zn metal as one of promising anode materials for aqueous batteries but suffers from disreputable dendrite growth, grievous hydrogen evolution and corrosion. Here, a polycation additive, polydiallyl dimethylammonium chloride (PDD), is introduced to achieve long‐term and highly reversible Zn plating/stripping. Specifically, the PDD can simultaneously regulate the electric fields of electrolyte and Zn/electrolyte interface to improve Zn 2+ migration behaviors and guide dominant Zn (002) deposition, which is veritably detected by Zeta potential, Kelvin probe force microscopy and scanning electrochemical microscopy. Moreover, PDD also creates a positive charge‐rich protective outer layer and a N‐rich hybrid inner layer, which accelerates the Zn 2+ desolvation during plating process and blocks the direct contact between water molecules and Zn anode. Thereby, the reversibility and long‐term stability of Zn anodes are substantially improved, as certified by a higher average coulombic efficiency of 99.7 % for Zn||Cu cells and 22 times longer life for Zn||Zn cells compared with that…

Abstract Electro‐reforming of Polyethylene‐terephthalate‐derived (PET‐derived) ethylene glycol (EG) into fine chemicals and H 2 is an ideal solution to address severe plastic pollution. Here, we report the electrooxidation of EG to glycolic acid (GA) with a high Faraday efficiency and selectivity (>85 %) even at an industry‐level current density (600 mA cm −2 at 1.15 V vs. RHE) over a Pd−Ni(OH) 2 catalyst. Notably, stable electrolysis over 200 h can be achieved, outperforming all available Pd‐based catalysts. Combined experimental and theoretical results reveal that 1) the OH* generation promoted by Ni(OH) 2 plays a critical role in facilitating EG‐to‐GA oxidation and removing poisonous carbonyl species, thereby achieving high activity and stability; 2) Pd with a downshifted d‐band center and the oxophilic Ni can synergistically facilitate the rapid desorption and transfer of GA from the active Pd sites to the inactive Ni sites, avoiding over‐oxidation and thus achieving high selectivity.

Abstract All‐solid‐state batteries (ASSBs) with inorganic solid electrolytes (SEs) have attracted significant interest as next‐generation energy storage. Halides such as Li 3 YCl 6 are promising candidates for SE because they combine high oxidation stability and deformability. However, the ionic conductivities of halide SEs are not as high as those of other SEs, especially sulfides. Here, we discover new lithium‐metal‐oxy‐halide materials, Li M OCl 4 ( M =Nb, Ta). They exhibit extremely high ionic conductivities of 10.4 mS cm −1 for M =Nb and 12.4 mS cm −1 for M =Ta, respectively, even in cold‐pressed powder forms at room temperature, which are comparable to or surpass those of organic liquid electrolytes used in lithium‐ion batteries. Bulk‐type ASSB cells using the oxyhalides as the cathode SE demonstrate an outstanding rate capability with a capacity retention of 80 % at 5 C/0.1 C. We believe that the proposed oxyhalides are promising SE candidates for the practical applications of ASSBs.

Abstract A highly selective and durable oxygen evolution reaction (OER) electrocatalyst is the bottleneck for direct seawater splitting because of side reactions primarily caused by chloride ions (Cl − ). Most studies about OER catalysts in seawater focus on the repulsion of the Cl − to reduce its negative effects. Herein, we demonstrate that the absorption of Cl − on the specific site of a popular OER electrocatalyst, nickel‐iron layered double hydroxide (NiFe LDH), does not have a significant negative impact; rather, it is beneficial for its activity and stability enhancement in natural seawater. A set of in situ characterization techniques reveals that the adsorption of Cl − on the desired Fe site suppresses Fe leaching, and creates more OER‐active Ni sites, improving the catalyst's long‐term stability and activity simultaneously. Therefore, we achieve direct alkaline seawater electrolysis for the very first time on a commercial‐scale alkaline electrolyser (AE, 120 cm 2 electrode area) using the NiFe LDH anode. The new alkaline seawater electrolyser exhibits a reduction in…

Abstract Fe−N−C catalysts with single‐atom Fe−N 4 configurations are highly needed owing to the high activity for oxygen reduction reaction (ORR). However, the limited intrinsic activity and dissatisfactory durability have significantly restrained the practical application of proton‐exchange membrane fuel cells (PEMFCs). Here, we demonstrate that constructing adjacent metal atomic clusters (ACs) is effective in boosting the ORR performance and stability of Fe−N 4 catalysts. The integration of Fe−N 4 configurations with highly uniform Co 4 ACs on the N‐doped carbon substrate (Co 4 @/Fe 1 @NC) is realized through a “pre‐constrained” strategy using Co 4 molecular clusters and Fe(acac) 3 implanted carbon precursors. The as‐developed Co 4 @/Fe 1 @NC catalyst exhibits excellent ORR activity with a half‐wave potential ( E 1/2 ) of 0.835 V vs. RHE in acidic media and a high peak power density of 840 mW cm −2 in a H 2 −O 2 fuel cell test. First‐principles calculations further clarify the ORR catalytic mechanism on the identified Fe−N 4 that modified with Co 4 ACs. This work provides a viable…

Abstract The large‐scale applicability of Zn‐metal anodes is severely impeded by the issues such as the dendrite growth, complicated hydrogen evolution, and uncontrollable passivation reaction. Herein, a negatively charged carboxylated double‐network hydrogel electrolyte (Gelatin/Sodium alginate‐acetate, denoted as Gel/SA‐acetate) has been developed to stabilize the interfacial electrochemistry, which restructures a type of Zn 2+ ion solvent sheath optimized via a chain‐liquid synergistic effect. New hydrogen bonds are reconstructed with water molecules by the zincophilic functional groups, and directional migration of hydrated Zn 2+ ions is therefore induced. Concomitantly, the robust chemical bonding of such hydrogel layers to the Zn slab exhibits a desirable anti‐catalytic effect, thereby greatly diminishing the water activity and eliminating side reactions. Subsequently, a symmetric cell using the Gel/SA‐acetate electrolyte demonstrates a reversible plating/stripping performance for 1580 h, and an asymmetric cell reaches a state‐of‐the‐art runtime of 5600 h with a high average…

Abstract Aqueous Zn‐Iodine (I 2 ) batteries are attractive for large‐scale energy storage. However, drawbacks include, Zn dendrites, hydrogen evolution reaction (HER), corrosion and, cathode “shuttle” of polyiodines. Here we report a class of N‐containing heterocyclic compounds as organic pH buffers to obviate these. We evidence that addition of pyridine /imidazole regulates electrolyte pH, and inhibits HER and anode corrosion. In addition, pyridine and imidazole preferentially absorb on Zn metal, regulating non‐dendritic Zn plating /stripping, and achieving a high Coulombic efficiency of 99.6 % and long‐term cycling stability of 3200 h at 2 mA cm −2 , 2 mAh cm −2 . It is also confirmed that pyridine inhibits polyiodines shuttling and boosts conversion kinetics for I − /I 2 . As a result, the Zn‐I 2 full battery exhibits long cycle stability of >25 000 cycles and high specific capacity of 105.5 mAh g −1 at 10 A g −1 . We conclude organic pH buffer engineering is practical for dendrite‐free and shuttle‐free Zn‐I 2 batteries.

Abstract The performance of aqueous Zn ion batteries (AZIBs) is highly dependent on inner Helmholtz plane (IHP) chemistry. Notorious parasitic reactions containing hydrogen evolution reactions (HER) and Zn dendrites both originate from abundant free H2O and random Zn deposition inside active IHP. Here, we report a universal high donor number (DN) additive pyridine (Py) with only 1 vol. % addition (Py‐to‐H2O volume ratio), for regulating molecule distribution inside IHP. Density functional theory (DFT) calculations and molecular dynamics (MD) simulation verify that incorporated Py additive could tailor Zn2+ solvation sheath and exclude H2O molecules from IHP effectively, which is in favor of preventing H2O decomposition. Consequently, even at extreme conditions such as high depth of discharge (DOD) of 80 %, the symmetric cell based on Py additive can sustain approximately 500 h long‐term stability. This efficient strategy with high DN additives furnishes a promising direction for designing novel electrolytes and promoting the practical application of AZIBs, despite inevitably…

Abstract Crystallography modulation of zinc (Zn) metal anode is promising to promote Zn reversibility in aqueous electrolytes, but efficiently constructing Zn with specific crystallographic texture remains challenging. Herein, we report a current‐controlled electrodeposition strategy to texture the Zn electrodeposits in conventional aqueous electrolytes. Using the electrolytic cell with low‐cost Zn(CH 3 COO) 2 electrolyte and Cu substrate as a model system, the texture of as‐deposited Zn gradually transforms from (101) to (002) crystal plane as increasing the current density from 20 to 80 mA cm −2 . Moreover, the high current accelerates the Zn nucleation rate with abundant nuclei, enabling uniform deposition. The (002) texture permits stronger resistance to dendrite growth and interfacial side reactions than the (101) texture. The resultant (002)‐textured Zn electrode achieves deep cycling stability and supports the stable operation of full batteries with conventional V/Mn‐based oxide cathodes.

Oxygen reduction reaction (ORR) is vital for clean and renewable energy technologies, which require no fossil fuel but catalysts. Platinum (Pt) is the best-known catalyst for ORR. However, its high cost and scarcity have severely hindered renewable energy devices (e.g., fuel cells) for large-scale applications. Recent breakthroughs in carbon-based metal-free electrochemical catalysts (C-MFECs) show great potential for earth-abundant carbon materials as low-cost metal-free electrocatalysts towards ORR in acidic media. This article provides a focused, but critical review on C-MFECs for ORR in acidic media with an emphasis on advances in the structure design and synthesis, fundamental understanding of the structure-property relationship and electrocatalytic mechanisms, and their applications in proton exchange membrane fuel cells. Current challenges and future perspectives in this emerging field are also discussed.

Abstract The development of productive catalysts for the oxygen evolution reaction (OER) remains a major challenge requiring significant progress in both mechanism and material design. Conventionally, the thermodynamic barrier of lattice oxidation mechanism (LOM) is lower than that of absorbate evolution mechanism (AEM) because the former can overcome certain limitations. However, controlling the OER pathway from the AEM to the LOM by exploiting the intrinsic properties of the catalyst remains challenging. Herein, we incorporated F anions into the oxygen vacancies of spinel ZnCo 2 O 4 and established a link between the electronic structure and the OER catalytic mechanism. Theoretical density calculations revealed that F upshifts the O 2p center and activates the redox capability of lattice O, successfully triggering the LOM pathway. Moreover, the high electronegativity of F anions is favourable for balancing the residual protonation, which can stabilize the structure of the catalyst.

Abstract Routine electrolyte additives are not effective enough for uniform zinc (Zn) deposition, because they are hard to proactively guide atomic‐level Zn deposition. Here, based on underpotential deposition (UPD), we propose an “escort effect” of electrolyte additives for uniform Zn deposition at the atomic level. With nickel ion (Ni2+) additives, we found that metallic Ni deposits preferentially and triggers the UPD of Zn on Ni. This facilitates firm nucleation and uniform growth of Zn while suppressing side reactions. Besides, Ni dissolves back into the electrolyte after Zn stripping with no influence on interfacial charge transfer resistance. Consequently, the optimized cell operates for over 900 h at 1 mA cm−2 (more than 4 times longer than the blank one). Moreover, the universality of “escort effect” is identified by using Cr3+ and Co2+ additives. This work would inspire a wide range of atomic‐level principles by controlling interfacial electrochemistry for various metal batteries.

Abstract Singlet oxygen ( 1 O 2 ) is an excellent reactive oxygen species (ROSs) for the selective conversion of organic matter, especially in advanced oxidation processes (AOPs). However, due to the huge dilemma in synthesizing single‐site type catalysts, the control and regulation of 1 O 2 generation in AOPs is still challenging and the underlying mechanism remains largely obscure. Here, taking advantage of the well‐defined and flexibly tunable sites of covalent organic frameworks (COFs), we report the first achievement in precisely regulating ROSs generation in peroxymonosulfate (PMS)‐based AOPs by site engineering of COFs. Remarkably, COFs with bipyridine units (BPY‐COFs) facilitate PMS activation via a nonradical pathway with 100 % 1 O 2 , whereas biphenyl‐based COFs (BPD‐COFs) with almost identical structures activate PMS to produce radicals (⋅OH and SO 4 .− ). The BPY‐COFs/PMS system delivers boosted performance for selective degradation of target pollutants from water, which is ca. 9.4 times that of its BPD‐COFs counterpart, surpassing most reported PMS‐based AOPs systems.…

Photopharmacology is an attractive approach for achieving targeted drug action with the use of light. In photopharmacology, molecular photoswitches are introduced into the structure of biologically active small molecules to allow for the optical control of their potency. Going beyond trial and error, photopharmacology has progressively applied rational drug design methodologies to devise light-controlled bioactive ligands. In this review, we categorize photopharmacological efforts from the standpoint of medicinal chemistry strategies, focusing on diffusible photochromic ligands modified with photoswitches that operate through E-Z bond isomerization. In the vast majority of cases, photoswitchable ligands are designed as analogs of existing compounds, through a variety of approaches. By analyzing in detail a comprehensive list of instructive examples, we describe the state of the art and discuss future opportunities for rational design in photopharmacology.

Abstract Heteroatom doping has emerged as a highly effective strategy to enhance the activity of metal‐based electrocatalysts toward the oxygen evolution reaction (OER). It is widely accepted that the doping does not switch the OER mechanism from the adsorbate evolution mechanism (AEM) to the lattice‐oxygen‐mediated mechanism (LOM), and the enhanced activity is attributed to the optimized binding energies toward oxygen intermediates. However, this seems inconsistent with the fact that the overpotential of doped OER electrocatalysts (<300 mV) is considerably smaller than the limit of AEM (>370 mV). To determine the origin of this inconsistency, we select phosphorus (P)‐doped nickel‐iron mixed oxides as the model electrocatalysts and observe that the doping enhances the covalency of the metal‐oxygen bonds to drive the OER pathway transition from the AEM to the LOM, thereby breaking the adsorption linear relation between *OH and *OOH in the AEM. Consequently, the obtained P‐doped oxides display a small overpotential of 237 mV at 10 mA cm −2 . Beyond P, the similar pathway transition is…

Abstract The renewable‐energy‐powered electroreduction of nitrate (NO3−) to ammonia (NH3) has garnered significant interest as an eco‐friendly and promising substitute for the Haber–Bosch process. However, the sluggish kinetics hinders its application at a large scale. Herein, we first calculated the N‐containing species (*NO3 and *NO2) binding energy and the free energy of the hydrogen evolution reaction over Cu with different metal dopants, and it was shown that Zn was a promising candidate. Based on the theoretical study, we designed and synthesized Zn‐doped Cu nanosheets, and the as‐prepared catalysts demonstrated excellent performance in NO3−‐to‐NH3. The maximum Faradaic efficiency (FE) of NH3 could reach 98.4 % with an outstanding yield rate of 5.8 mol g−1 h−1, which is among the best results up to date. The catalyst also had excellent cycling stability. Meanwhile, it also presented a FE exceeding 90 % across a wide potential range and NO3− concentration range. Detailed experimental and theoretical studies revealed that the Zn doping could modulate intermediates adsorption…

Hydrocarbon conversion catalysts suffer from deactivation by deposition or formation of carbon deposits. Carbon deposit formation is thermodynamically favored above 350 °C, even in some hydrogen-rich environments. We discuss four basic mechanisms: a carbenium-ion based mechanism taking place on acid sites of zeolites or bifunctional catalysts, a metal-induced formation of soft coke (i.e., oligomers of small olefins) on bifunctional catalysts, a radical-mediated mechanism in higher-temperature processes, and fast-growing carbon filament formation. Catalysts deactivate because carbon deposits block pores at different length scales, or directly block active sites. Some deactivated catalysts can be re-used, others can be regenerated or have to be discarded. Catalyst and process design can mitigate the effects of deactivation. New analytical tools allow for the direct observation (in some cases even under in situ or operando conditions) of the 3D-distribution of coke-type species as a function of catalyst structure and lifetime.

Abstract Seawater electrolysis is an attractive way of making H2 in coastal areas, and NiFe‐based materials are among the top options for alkaline seawater oxidation (ASO). However, ample Cl− in seawater can severely corrode catalytic sites and lead to limited lifespans. Herein, we report that in situ carbon oxyanion self‐transformation (COST) from oxalate to carbonate on a monolithic NiFe oxalate micropillar electrode allows safeguard of high‐valence metal reaction sites in ASO. In situ/ex situ studies show that spontaneous, timely, and appropriate COST safeguards active sites against Cl− attack during ASO even at an ampere‐level current density (j). Our NiFe catalyst shows efficient and stable ASO performance, which requires an overpotential as low as 349 mV to attain a j of 1 A cm−2. Moreover, the NiFe catalyst with protective surface CO32− exhibits a slight activity degradation after 600 h of electrolysis under 1 A cm−2 in alkaline seawater. This work reports effective catalyst surface design concepts at the level of oxyanion self‐transformation, acting as a momentous step…

Abstract Metal–organic frameworks (MOFs) have been increasingly applied in oxygen evolution reaction (OER), and the surface of MOFs usually undergoes structural transformation to form metal oxyhydroxides to serve as catalytically active sites. However, the controllable regulation of the reconstruction process of MOFs remains as a great challenge. Here we report a defect engineering strategy to facilitate the structural transformation of MOFs to metal oxyhydroxides during OER with enhanced activity. Defective MOFs (denoted as NiFc′ x Fc 1‐x ) with abundant unsaturated metal sites are constructed by mixing ligands of 1,1′‐ferrocene dicarboxylic acid (Fc′) and defective ferrocene carboxylic acid (Fc). NiFc′ x Fc 1‐x series are more prone to be transformed to metal oxyhydroxides compared with the non‐defective MOFs (NiFc′). Moreover, the as‐formed metal oxyhydroxides derived from defective MOFs contain more oxygen vacancies. NiFc′Fc grown on nickel foam exhibits excellent OER catalytic activity with an overpotential of 213 mV at the current density of 100 mA cm −2 , superior to that of…

Abstract Solar‐driven synthesis of hydrogen peroxide (H 2 O 2 ) from water and air provides a low‐cost and eco‐friendly alternative route to the traditional anthraquinone method. Herein, four thiazole‐based conjugated polymers (Tz‐CPs: TTz , BTz , TBTz and BBTz ) are synthesized via aldimine condensation. BBTz exhibits the highest H 2 O 2 production rate of 7274 μmol g −1 h −1 in pure water. Further, the reaction path is analyzed by electron paramagnetic resonance (EPR), in situ diffuse reflectance infrared Fourier transform (DRIFT) and theoretical calculation, highlighting the prominent role of singlet oxygen ( 1 O 2 ). The generation of 1 O 2 occurs through the oxidation of superoxide radical (⋅O 2 − ) and subsequent conversion into endoperoxides via [4+2] cycloaddition over BBTz , which promotes charge separation and reduces the barrier for H 2 O 2 production. This work provides new insight into the mechanism of photocatalytic O 2 reduction and the molecular design of superior single‐polymer photocatalysts.

Single-atom catalysts hold the potential to significantly impact the chemical sector, pushing the boundaries of catalysis in new, uncharted directions. These materials, featuring isolated metal species ligated on solid supports, can exist in many coordination environments, all of which have shown important functions in specific transformations. Their emergence has also provided exciting opportunities for mimicking metalloenzymes and bridging the gap between homogeneous and heterogeneous catalysis. This Review outlines the impressive progress made in recent years regarding the use of single-atom catalysts in organic synthesis. We also illustrate potential knowledge gaps in the search for more sustainable, earth-abundant single-atom catalysts for synthetic applications.

The pursuit of high metal utilization in heterogeneous catalysis has triggered the burgeoning interest of various atomically dispersed catalysts. Our aim in this review is to assess key recent findings in the synthesis, characterization, structure-property relationship and computational studies of dual-atom catalysts (DACs), which cover the full spectrum of applications in thermocatalysis, electrocatalysis and photocatalysis. In particular, combination of qualitative and quantitative characterization with cooperation with DFT insights, synergies and superiorities of DACs compare to counterparts, high-throughput catalyst exploration and screening with machine-learning algorithms are highlighted. Undoubtably, it would be wise to expect more fascinating developments in the field of DACs as tunable catalysts.

Abstract Nanozymes aim to mimic the highly evolved active centers of natural enzymes. Despite progress in nanozyme engineering, their catalytic performance is much less favorable compared with natural enzymes. This study shows that precise control over the atomic configuration of the active centers of Co single‐atom nanozymes (SAzymes) enables the rational regulation of their catalase‐like performance guided by theorical calculations. The constructed Co‐N3PS SAzyme exhibits an excellent catalase‐like activity and kinetics, exceeding the representative controls of Co‐based SAzymes with different atomic configurations. Moreover, we developed an ordered structure‐oriented coordination design strategy for rationally engineering SAzymes and established a correlation between the structure and enzyme‐like performance. This work demonstrates that precise control over the active centers of SAzymes is an efficient strategy to mimic the highly evolved active sites of natural enzymes.

Abstract Cooperative coupling of H 2 evolution with oxidative organic synthesis is promising in avoiding the use of sacrificial agents and producing hydrogen energy with value‐added chemicals simultaneously. Nonetheless, the photocatalytic activity is obstructed by sluggish electron‐hole separation and limited redox potentials. Herein, Ni‐doped Zn 0.2 Cd 0.8 S quantum dots are chosen after screening by DFT simulation to couple with TiO 2 microspheres, forming a step‐scheme heterojunction. The Ni‐doped configuration tunes the highly active S site for augmented H 2 evolution, and the interfacial Ni−O bonds provide fast channels at the atomic level to lower the energy barrier for charge transfer. Also, DFT calculations reveal an enhanced built‐in electric field in the heterojunction for superior charge migration and separation. Kinetic analysis by femtosecond transient absorption spectra demonstrates that expedited charge migration with electrons first transfer to Ni 2+ and then to S sites. Therefore, the designed catalyst delivers drastically elevated H 2 yield (4.55 mmol g −1 h −1 )…

Abstract Solvothermal reaction of 5,5′‐(pyridine‐2,6‐diylbis(oxy))diisophthalic acid (H 4 L) with europium(III) or terbium(III) nitrates in acetonitrile‐water (1 : 1) at 120 °C gave rise to isostructural 2D coordination polymers, [Ln(HL)(H 2 O) 3 ] ∞ ( NIIC‐1‐Eu and NIIC‐1‐Tb ), the layers of which are composed by eight‐coordinated lanthanide(III) ions interconnected by triply deprotonated ligands HL 3− . The layers are packed in the crystal without any specific intermolecular interactions between them, allowing the facile preparation of stable water suspensions, in which NIIC‐1‐Tb exhibited top‐performing sensing properties through luminescence quenching effect with exceptionally low detection limits towards Fe 3+ (LOD 8.62 nM), ofloxacin (OFX) antibiotic (LOD 3.91 nM) and cotton phytotoxicant gossypol (LOD 2.27 nM). In addition to low detection limit and high selectivity, NIIC‐1‐Tb features fast sensing response (within 60–90 seconds), making it superior to other MOF‐based sensors for metal cations and organic toxicants. The photoluminescence quantum yield of NIIC‐1‐Tb was 93 %,…

Abstract The insufficient exciton (e−‐h+ pair) separation/transfer and sluggish two‐electron water oxidation are two main factors limiting the H2O2 photosynthetic efficiency of covalent organic frameworks (COFs) photocatalysts. Herein, we present an alternative strategy to simultaneously facilitate exciton separation/transfer and reduce the energy barrier of two‐electron water oxidation in COFs via a dicyano functionalization. The in situ characterization and theoretical calculations reveal that the dicyano functionalization improves the amount of charge transfer channels between donor and acceptor units from two in COF‐0CN without cyano functionalization to three in COF‐1CN with mono‐cyano functionalization and four in COF‐2CN with dicyano functionalization, leading to the highest separation/transfer efficiency in COF‐2CN. More importantly, the dicyano group activates the neighbouring C atom to produce the key *OH intermediate for effectively reducing the energy barrier of rate‐determining two‐electron water oxidation in H2O2 photosynthesis. The simultaneously enhanced exciton…

Abstract Rational design of low‐cost and efficient transition‐metal catalysts for low‐temperature CO 2 activation is significant and poses great challenges. Herein, a strategy via regulating the local electron density of active sites is developed to boost CO 2 methanation that normally requires >350 °C for commercial Ni catalysts. An optimal Ni/ZrO 2 catalyst affords an excellent low‐temperature performance hitherto, with a CO 2 conversion of 84.0 %, CH 4 selectivity of 98.6 % even at 230 °C and GHSV of 12,000 mL g −1 h −1 for 106 h, reflecting one of the best CO 2 methanation performance to date on Ni‐based catalysts. Combined a series of in situ spectroscopic characterization studies reveal that re‐constructing monoclinic ‐ZrO 2 supported Ni species with abundant oxygen vacancies can facilitate CO 2 activation, owing to the enhanced local electron density of Ni induced by the strong metal‐support interactions. These findings might be of great aid for construction of robust catalysts with an enhanced performance for CO 2 emission abatement and beyond.

Abstract As a burgeoning electrolyte system, eutectic electrolytes based on ZnCl 2 /Zn(CF 3 SO 3 ) 2 /Zn(TFSI) 2 have been widely proposed in advanced Zn‐I 2 batteries; however, safety and cost concerns significantly limit their applications. Here, we report new‐type ZnSO 4 ‐based eutectic electrolytes that are both safe and cost‐effective. Their universality is evident in various solvents of polyhydric alcohols, in which multiple −OH groups not only involve in Zn 2+ solvation but also interact with water, resulting in the high stability of electrolytes. Taking propylene glycol‐based hydrated eutectic electrolyte as an example, it features significant advantages in non‐flammability and low price that is <1/200 cost of Zn(CF 3 SO 3 ) 2 /Zn(TFSI) 2 ‐based eutectic electrolytes. Moreover, its effectiveness in confining the shuttle effects of I 2 cathode and side reactions of Zn anodes is evidenced, resulting in Zn‐I 2 cells with high reversibility at 1 C and 91.4 % capacity remaining under 20 C. After scaling up to the pouch cell with a record mass loading of 33.3 mg cm −2 ,…

Abstract Electricity‐driven organo‐oxidations have shown an increasing potential recently. However, oxygen evolution reaction (OER) is the primary competitive reaction, especially under high current densities, which leads to low Faradaic efficiency (FE) of the product and catalyst detachment from the electrode. Here, we report a bimetallic Ni−Cu electrocatalyst supported on Ni foam (Ni−Cu/NF) to passivate the OER process while the oxidation of 5‐hydroxymethylfurfural (HMF) is significantly enhanced. A current density of 1000 mA cm −2 can be achieved at 1.50 V vs . reversible hydrogen electrode, and both FE and yield keep close to 100 % over a wide range of potentials. Both experimental results and theoretical calculations reveal that Cu doping impedes the OH* deprotonation to O* and hereby OER process is greatly passivated. Those instructive results provide a new approach to realizing highly efficient biomass upgrading by regulating the OER activity.

Abstract The slow water dissociation process in alkaline electrolyte severely limits the kinetics of HER. The orientation of H 2 O is well known to affect the dissociation process, but H 2 O orientation is hard to control because of its random distribution. Herein, an atomically asymmetric local electric field was designed by IrRu dizygotic single‐atom sites (IrRu DSACs) to tune the H 2 O adsorption configuration and orientation, thus optimizing its dissociation process. The electric field intensity of IrRu DSACs is over 4.00×10 10 N/C. The ab initio molecular dynamics simulations combined with in situ Raman spectroscopy analysis on the adsorption behavior of H 2 O show that the M−H bond length (M=active site) is shortened at the interface due to the strong local electric field gradient and the optimized water orientation promotes the dissociation process of interfacial water. This work provides a new way to explore the role of single atomic sites in alkaline hydrogen evolution reaction.

Abstract The positive liquid crystals, 4′‐heptyl‐4‐biphenylcarbonitrile (7CB), are used to functionalize carbon nanotubes (LC‐CNT), which can be aligned in the liquid crystalline polyimide (LC‐PI) matrix under an alternating electric field to fabricate the thermally conductive LC‐CNT/LC‐PI composite films. The efficient establishment of thermal conduction pathways in thermally conductive LC‐CNT/LC‐PI composite films with a low amount of LC‐CNT is achieved through the oriented alignment of LC‐CNT within the LC‐PI matrix. When the mass fraction of LC‐CNT is 15 wt %, the in‐plane thermal conductivity coefficient ( λ ∥ ) and the through‐plane thermal conductivity coefficient ( λ ⊥ ) of the LC‐CNT/LC‐PI composite films reach 4.02 W/(m ⋅ K) and 0.55 W/(m⋅K), which are 90.5 % and 71.9 % higher than those of the intrinsically thermally conductive LC‐PI films respectively, also 28.8 % and 5.8 % higher than those of the CNT/LC‐PI composite films respectively. Meanwhile, the thermally conductive LC‐CNT/LC‐PI composite films also possess excellent mechanical and heat resistance properties. The…

-based high-nickel layered oxide cathodes are regarded as promising cathode materials for high-energy-density automotive lithium batteries. Most of the attention thus far has been paid towards addressing their surface and structural instability issues brought by the increase of Ni content (>90 %) with an aim to enhance the cycle stability. However, the poor safety performance remains an intractable problem for their commercialization in the market, yet it has not received appropriate attention. In this review, we focus on the gas generation and thermal degradation behaviors of high-Ni cathodes, which are critical factors in determining their overall safety performance. A comprehensive overview of the mechanisms of outgassing and thermal runaway reactions is presented and analyzed from a chemistry perspective. Finally, we discuss the challenges and the insights into developing robust, safe high-Ni cathodes.

Abstract Oxygen vacancies‐enriched black TiO 2 is one promising support for enhancing hydrogen evolution reaction (HER). Herein, oxygen vacancies enriched black TiO 2 supported sub‐nanometer Pt clusters (Pt/TiO 2 ‐O V ) with metal support interactions is designed through solvent‐free microwave and following low‐temperature electroless approach for the first time. High‐temperature and strong reductants are not required and then can avoid the aggregation of decorated Pt species. Experimental and theoretical calculation verify that the created oxygen vacancies and Pt clusters exhibit synergistic effects for optimizing the reaction kinetics. Based on it, Pt/TiO 2 ‐O V presents remarkable electrocatalytic performance with 18 mV to achieve 10 mA cm −2 coupled with small Tafel slope of 12 mV dec −1 . This work provides quick synthetic strategy for preparing black titanium dioxide based nanomaterials.

Abstract How to transfer industrial exhaust gases of nitrogen oxides into high‐values product is significantly important and challenging. Herein, we demonstrate an innovative method for artificial synthesis of essential α‐amino acids from nitric oxide (NO) by reacting with α‐keto acids through electrocatalytic process with atomically dispersed Fe supported on N‐doped carbon matrix (AD‐Fe/NC) as the catalyst. A yield of valine with 32.1 μmol mg cat −1 is delivered at −0.6 V vs . reversible hydrogen electrode, corresponding a selectivity of 11.3 %. In situ X‐ray absorption fine structure and synchrotron radiation infrared spectroscopy analyses show that NO as nitrogen source converted to hydroxylamine that promptly nucleophilic attacked on the electrophilic carbon center of α‐keto acid to form oxime and subsequent reductive hydrogenation occurred on the way to amino acid. Over 6 kinds of α‐amino acids have been successfully synthesized and gaseous nitrogen source can be also replaced by liquid nitrogen source (NO 3 − ). Our findings not only provide a creative method for converting…

Abstract Aiming to improve the photocatalytic activity in N 2 fixation to produce ammonia, herein, we proposed a photochemical strategy to fabricate defects, and further deposition of Ru single atoms onto UiO‐66 (Zr) framework. Electron‐metal‐support interactions (EMSI) were built between Ru single atoms and the support via a covalently bonding. EMSI were capable of accelerating charge transfer between Ru SAs and UiO‐66, which was favorable for highly‐efficiently photocatalytic activity. The photocatalytic production rate of ammonia improved from 4.57 μmol g −1 h −1 to 16.28 μmol g −1 h −1 with the fabrication of defects onto UiO‐66, and further to 53.28 μmol g −1 h −1 with Ru‐single atoms loading. From the DFT results, it was found that d ‐orbital electrons of Ru were donated to N 2 π✶‐antibonding orbital, facilitating the activation of the N≡N triple bond. A distal reaction pathway was probably occurred for the photocatalytic N 2 reduction to ammonia on Ru 1 /d‐UiO‐66 (single Ru sites decorated onto the nodes of defective UiO‐66), and the first step of hydrogenation of N 2 was the…

Recent years have seen the emergence of capacitive deionization (CDI) as a promising desalination technique for converting sea and wastewater into potable water, due to its energy efficiency and eco-friendly nature. However, its low salt removal capacity and parasitic reactions have limited its effectiveness. As a result, the development of porous carbon nanomaterials as electrode materials have been explored, while taking into account of material characteristics such as morphology, wettability, high conductivity, chemical robustness, cyclic stability, specific surface area, and ease of production. To tackle the parasitic reaction issue, membrane capacitive deionization (mCDI) was proposed which utilizes ion-exchange membranes coupled to the electrode. Fabrication techniques along with the experimental parameters used to evaluate the desalination performance of different materials are discussed in this review to provide an overview of improvements made for CDI and mCDI desalination purposes.

Abstract Supramolecular interactions facilitate the development of tough multifunctional thermoplastic elastomers. However, the fundamental principles that govern supramolecular toughening are barely understood, and the rational design to achieve the desired high toughness remains daunting. Herein, we report a simple and robust method for toughening thermoplastic elastomers by rationally tailoring hard–soft phase separation structures containing rigid and flexible supramolecular segments. The introduced functional segments with distinct structural rigidities provide mismatched supramolecular interactions to efficiently tune the energy dissipation and bear an external load. The optimal supramolecular elastomer containing aromatic amide and acylsemicarbazide moieties demonstrates a record toughness (1.2 GJ m −3 ), extraordinary crack tolerance (fracture energy 282.5 kJ m −2 ), an ultrahigh true stress at break (2.3 GPa), good elasticity, healing ability, recyclability, and impact resistance. The toughening mechanism is validated by testing various elastomers, confirming the potential…

Cancer is one of the deadliest diseases worldwide. Recent statistics have shown that metastases and tumor relapse are the leading causes of cancer-associated deaths. While traditional treatments are able to efficiently remove the primary tumor, secondary tumors remain poorly accessible. Capitalizing on this there is an urgent need for novel treatment modalities. Among the most promising approaches, increasing research interest has been devoted to immunogenic cell death inducing agents that are able to trigger localized cell death of the cancer cells as well as induce an immune response inside the whole organism. Preliminary studies have shown that immunogenic cell death inducing compounds could be able to overcome metastatic and relapsing tumors. Herein, the application of metal complexes as immunogenic cell death inducing compounds is systematically reviewed.

Abstract Zinc (Zn) metal anode suffers from uncontrollable Zn dendrites and parasitic side reactions at the interface, which restrict the practical application of aqueous rechargeable zinc batteries (ARZBs). Herein, an amphoteric cellulose‐based double‐network is introduced as hydrogel electrolyte to overcome these obstacles. On one hand, the amphoteric groups build anion/cation transport channels to regulate electro‐deposition behavior on Zn (002) crystal plane enabled by homogenizing Zn 2+ ions flux. On the other hand, the strong bonding between negatively charged carboxyl groups and Zn 2+ ions promote the desolvation process of [Zn(H 2 O) 6 ] 2+ to eliminate side reactions. Based on the above two functions, the hydrogel electrolyte enables an ultra‐stable cycling with a cumulative capacity of 7 Ah cm −2 at 20 mA cm −2 /20 mAh cm −2 for Zn||Zn cell. This work provides significant concepts for developing hydrogel electrolytes to realize stable anode for high‐performance ARZBs.

The moderate reversibility of Zn anodes, as a long-standing challenge in aqueous zinc-ion batteries, promotes the exploration of suitable electrolyte additives continuously. It is crucial to establish the absolute predominance of smooth deposition within multiple interfacial reactions for stable zinc anodes, including suppressing side parasitic reactions and facilitating Zn plating process. Trehalose catches our attention due to the reported mechanisms in sustaining biological stabilization. In this work, the inter-disciplinary application of trehalose is reported in the electrolyte modification for the first time. The pivotal roles of trehalose in suppressed hydrogen evolution and accelerated Zn deposition have been investigated based on the principles of thermodynamics as well as reaction kinetics. The electrodeposit changes from random accumulation of flakes to dense bulk with (002)-plane exposure due to the unlocked crystal-face oriented deposition with trehalose addition. As a result, the highly reversible Zn anode is obtained, exhibiting a high average CE of 99.8 % in the…

Abstract Enhancing the peroxymonosulfate (PMS) activation efficiency to generate more radicals is vital to promote the Fenton‐like reaction activity, however, how to promote the PMS adsorption and accelerate the interfacial electron transfer to boost its activation kinetics remains a great challenge. Herein, we prepared Cu‐doped defect‐rich In 2 O 3 (Cu‐In 2 O 3 /O v ) catalysts containing asymmetric Cu−O v −In sites for PMS activation in water purification. The intrinsic catalytic activity is that the side‐on adsorption configuration of the O−O bond (Cu−O−O−In) at the Cu‐O v ‐In sites significantly stretches the O−O bond length. Meanwhile, the Cu‐O v ‐In sites increase the electron density near the Fermi energy level, promoting more and faster electron transfer to the O−O bond for generating more SO 4 ⋅ − and ⋅OH. The degradation rate constant of tetracycline achieved by Cu‐In 2 O 3 /O v is 31.8 times faster than In 2 O 3 /O v , and it shows the possibility of membrane reactor for practical wastewater treatment.

Abstract Electrochemical CO 2 reduction reaction (CO 2 RR) to chemical fuels such as formate offers a promising pathway to carbon‐neutral future, but its practical application is largely inhibited by the lack of effective activation of CO 2 molecules and pH‐universal feasibility. Here, we report an electronic structure manipulation strategy to electron‐rich Bi nanosheets, where electrons transfer from Cu donor to Bi acceptor in bimetallic Cu−Bi, enabling CO 2 RR towards formate with concurrent high activity, selectivity and stability in pH‐universal (acidic, neutral and alkaline) electrolytes. Combined in situ Raman spectra and computational calculations unravel that electron‐rich Bi promotes CO 2 ⋅ − formation to activate CO 2 molecules, and enhance the adsorption strength of *OCHO intermediate with an up‐shifted p ‐band center, thus leading to its superior activity and selectivity of formate. Further integration of the robust electron‐rich Bi nanosheets into III–V‐based photovoltaic solar cell results in an unassisted artificial leaf with a high solar‐to‐formate (STF) efficiency…

Abstract High‐valent metal‐oxo (HVMO) species are powerful non‐radical reactive species that enhance advanced oxidation processes (AOPs) due to their long half‐lives and high selectivity towards recalcitrant water pollutants with electron‐donating groups. However, high‐valent cobalt‐oxo (Co IV =O) generation is challenging in peroxymonosulfate (PMS)‐based AOPs because the high 3d‐orbital occupancy of cobalt would disfavor its binding with a terminal oxygen ligand. Herein, we propose a strategy to construct isolated Co sites with unique N 1 O 2 coordination on the Mn 3 O 4 surface. The asymmetric N 1 O 2 configuration is able to accept electrons from the Co 3d‐orbital, resulting in significant electronic delocalization at Co sites for promoted PMS adsorption, dissociation and subsequent generation of Co IV =O species. CoN 1 O 2 /Mn 3 O 4 exhibits high intrinsic activity in PMS activation and sulfamethoxazole (SMX) degradation, highly outperforming its counterpart with a CoO 3 configuration, carbon‐based single‐atom catalysts with CoN 4 configuration, and commercial cobalt oxides. Co…

Abstract Electrocatalytic nitrate reduction sustainably produces ammonia and alleviates water pollution, yet is still challenging due to the kinetic mismatch and hydrogen evolution competition. Cu/Cu 2 O heterojunction is proven effective to break the rate‐determining NO 3 − ‐to‐NO 2 − step for efficient NH 3 conversion, while it is unstable due to electrochemical reconstruction. Here we report a programmable pulsed electrolysis strategy to achieve reliable Cu/Cu 2 O structure, where Cu is oxidized to CuO during oxidation pulse, then regenerating Cu/Cu 2 O upon reduction. Alloying with Ni further modulates hydrogen adsorption, which transfers from Ni/Ni(OH) 2 to N‐containing intermediates on Cu/Cu 2 O, promoting NH 3 formation with a high NO 3 − ‐to‐NH 3 Faraday efficiency (88.0±1.6 %, pH 12) and NH 3 yield rate (583.6±2.4 μmol cm −2 h −1 ) under optimal pulsed conditions. This work provides new insights to in situ electrochemically regulate catalysts for NO 3 − ‐to‐NH 3 conversion.

Abstract Electrocatalytic CO2 reduction reaction (CO2RR) to multi‐carbon products (C2+) in acidic electrolyte is one of the most advanced routes for tackling our current climate and energy crisis. However, the competing hydrogen evolution reaction (HER) and the poor selectivity towards the valuable C2+ products are the major obstacles for the upscaling of these technologies. High local potassium ions (K+) concentration at the cathode's surface can inhibit proton‐diffusion and accelerate the desirable carbon‐carbon (C−C) coupling process. However, the solubility limit of potassium salts in bulk solution constrains the maximum achievable K+ concentration at the reaction sites and thus the overall acidic CO2RR performance of most electrocatalysts. In this work, we demonstrate that Cu nanoneedles induce ultrahigh local K+ concentrations (4.22 M) – thus breaking the K+ solubility limit (3.5 M) – which enables a highly efficient CO2RR in 3 M KCl at pH=1. As a result, a Faradaic efficiency of 90.69±2.15 % for C2+ (FEC2+) can be achieved at 1400 mA.cm−2, simultaneous with a single pass…

The photoactivation of electron donor-acceptor complexes has emerged as a sustainable, selective and versatile strategy for the generation of radical species. Electron donor-acceptor (EDA) complexation, however, imposes electronic constraints on the donor and acceptor components and this can limit the range of radicals that can be generated using the approach. New EDA complexation strategies exploiting sulfonium salts allow radicals to be generated from native functionality. For example, aryl sulfonium salts, formed by the activation of arenes, can serve as the acceptor components in EDA complexes due to their electron-deficient nature. This "sulfonium tag" approach relaxes the electronic constraints on the parent substrate and dramatically expands the range of radicals that can be generated using EDA complexation. In this review, these new applications of sulfonium salts will be introduced and the areas of chemical space rendered accessible through this innovation will be highlighted.

Abstract The construction of high‐activity and low‐cost electrocatalysts is critical for efficient hydrogen production by water electrolysis. Herein, we developed an advanced electrocatalyst by anchoring well‐dispersed Ir nanoparticles on nickel metal‐organic framework (MOF) Ni‐NDC (NDC: 2,6‐naphthalenedicarboxylic) nanosheets. Benefiting from the strong synergy between Ir and MOF through interfacial Ni−O−Ir bonds, the synthesized Ir@Ni‐NDC showed exceptional electrocatalytic performance for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and overall water splitting in a wide pH range, superior to commercial benchmarks and most reported electrocatalysts. Theoretical calculations revealed that the charge redistribution of Ni−O−Ir bridge induced the optimization of H 2 O, OH* and H* adsorption, thus leading to the accelerated electrochemical kinetics for HER and OER. This work provides a new clue to exploit bifunctional electrocatalysts for pH‐universal overall water splitting.

Polymerase chain reaction (PCR)-based nucleic acid testing has played a critical role in disease diagnostics, pathogen surveillance, and many more. However, this method requires a long turnaround time, expensive equipment, and trained personnel, limiting its widespread availability and diagnostic capacity. On the other hand, the clustered regularly interspaced short palindromic repeats (CRISPR) technology has recently demonstrated capability for nucleic acid detection with high sensitivity and specificity. CRISPR-mediated biosensing holds great promise for revolutionizing nucleic acid testing procedures and developing point-of-care diagnostics. This review focuses on recent developments in both fundamental CRISPR biochemistry and CRISPR-based nucleic acid detection techniques. Four ongoing research hotspots in molecular diagnostics-target preamplification-free detection, microRNA (miRNA) testing, non-nucleic-acid detection, and SARS-CoV-2 detection-are also covered.

Abstract Generating Fe IV =O on single‐atom catalysts by Fenton‐like reaction has been established for water treatment; however, the Fe IV =O generation pathway and oxidation behavior remain obscure. Employing an Fe−N−C catalyst with a typical Fe−N 4 moiety to activate peroxymonosulfate (PMS), we demonstrate that generating Fe IV =O is mediated by an Fe−N−C−PMS* complex—a well‐recognized nonradical species for induction of electron‐transfer oxidation—and we determined that adjacent Fe sites with a specific Fe 1 −Fe 1 distance are required. After the Fe atoms with an Fe 1 ‐Fe 1 distance <4 Å are PMS‐saturated, Fe−N−C−PMS* formed on Fe sites with an Fe 1 ‐Fe 1 distance of 4–5 Å can coordinate with the adjacent Fe II −N 4 , forming an inter‐complex with enhanced charge transfer to produce Fe IV =O. Fe IV =O enables the Fenton‐like system to efficiently oxidize various pollutants in a substrate‐specific, pH‐tolerant, and sustainable manner, where its prominent contribution manifests for pollutants with higher one‐electron oxidation potential.

Thermally activated delayed fluorescence (TADF) materials have attracted great potential in the field of organic light-emitting diodes (OLEDs). Among thousands of TADF materials, highly twisted TADF emitters have become a hotspot in recent years. Compared with traditional TADF materials, highly twisted TADF emitters tend to show multi-channel charge-transfer characters and form rigid molecular structures. This is advantageous for TADF materials, as non-radiative decay processes can be suppressed to facilitate efficient exciton utilization. Accordingly, OLEDs with excellent device performances have also been reported. In this Review, we have summarized recent progress in highly twisted TADF materials and related devices, and give an overview of the molecular design strategies, photophysical studies, and the performances of OLED devices. In addition, the challenges and perspectives of highly twisted TADF molecules and the related OLEDs are also discussed.

Abstract A chemically stable 2D microporous COF ( PMCR‐1 ) was synthesized via the multicomponent Povarov reaction. PMCR‐1 exhibits a remarkable and long‐term stable photocatalytic H 2 O 2 production rate (60 h) from pure and sea water under visible light. The H 2 O 2 production is markedly enhanced when benzyl alcohol (BA) is added as reductant, which is also due to a strong π–π interaction of BA with dangling phenyl moieties in the COF pores introduced by the multicomponent Povarov reaction. Motivated by the concomitant BA oxidation to benzaldehyde during H 2 O 2 formation, the photocatalytic oxidation of various organic substrates such as benzyl amine and methyl sulfide derivatives was investigated. It is shown that the well‐defined micropores of PMCR‐1 enable size‐selective photocatalytic oxidation.

Abstract Anion exchange membrane fuel cells (AEMFCs) and water electrolysis (AEMWE) show great application potential in the field of hydrogen energy conversion technology. However, scalable anion exchange membranes (AEMs) with desirable properties are still lacking, which greatly hampers the commercialization of this technology. Herein, we propose a series of novel multiblock AEMs based on ether‐free poly(biphenyl ammonium‐b‐biphenyl phenyl)s (PBPA‐b‐BPPs) that are suitable for use in high performance AEMFC and AEMWE systems because of their well‐formed microphase separation structures. The developed AEMs achieved outstanding OH − conductivity (162.2 mS cm −1 at 80 °C) with a low swelling ratio, good alkaline stability, and excellent mechanical durability (tensile strength >31 MPa and elongation at break >147 % after treatment in 2 M NaOH at 80 °C for 3750 h). A PBPA‐b‐BPP‐based AEMFC demonstrated a remarkable peak power density of 2.41 W cm −2 and in situ durability for 330 h under 0.6 A cm −2 at 70 °C. An AEMWE device showed a promising performance (6.25 A cm −2 at 2 V, 80 °C) and…

Abstract Singlet oxygen ( 1 O 2 ) is ubiquitously involved in various photocatalytic oxidation reactions; however, efficient and selective production of 1 O 2 is still challenging. Herein, we reported the synthesis of nickel porphyrin‐based covalent organic frameworks (COFs) incorporating functional groups with different electron‐donating/‐withdrawing features on their pore walls. These functional groups established a dedicated outer‐sphere microenvironment surrounding the Ni catalytic center that tunes the activity of the COFs for 1 O 2 ‐mediated thioether oxidation. With the increase of the electron‐donating ability of functional groups, the modulated outer‐sphere microenvironment turns on the catalytic activity from a yield of nearly zero by the cyano group functionalized COF to an excellent yield of 98 % by the methoxy group functionalized one. Electronic property investigation and density‐functional theory (DFT) calculations suggested that the distinct excitonic behaviors attributed to the diverse band energy levels and orbital compositions are responsible for the different…

The discovery of the medicinal properties of gold complexes has fuelled the design and synthesis of new anticancer metallodrugs, which have received special attention due to their unique modes of action. Current research in the development of gold compounds with therapeutic properties is predominantly focused on the molecular design of drug leads with superior pharmacological activities, e.g., by introducing targeting features. Moreover, intensive research aims at improving the physicochemical properties of gold compounds, such as chemical stability and solubility in the physiological environment. In this regard, the encapsulation of gold compounds in nanocarriers or their chemical grafting onto targeted delivery vectors could lead to new nanomedicines that eventually reach clinical applications. Herein, we provide an overview of the state-of-the-art progress of gold anticancer compounds, andmore importantly we thoroughly revise the development of nanoparticle-based delivery systems for gold chemotherapeutics.

Abstract Aqueous rechargeable zinc‐ion batteries (ARZBs) are impeded by the mutual problems of unstable cathode, electrolyte parasitic reactions, and dendritic growth of zinc (Zn) anode. Herein, a triple‐functional strategy by introducing the tetramethylene sulfone (TMS) to form a hydrated eutectic electrolyte is reported to ameliorate these issues. The activity of H 2 O is inhibited by reconstructing hydrogen bonds due to the strong interaction between TMS and H 2 O. Meanwhile, the preferentially adsorbed TMS on the Zn surface increases the thickness of double electric layer (EDL) structure, which provides a shielding buffer layer to suppress dendrite growth. Interestingly, TMS modulates the primary solvation shell of Zn 2+ ultimately to achieve a novel solvent co‐intercalation ((Zn‐TMS) 2+ ) mechanism, and the intercalated TMS works as a “pillar” that provides more zincophilic sites and stabilizes the structure of cathode (NH 4 V 4 O 10 , (NVO)). Consequently, the Zn||NVO battery exhibits a remarkably high specific capacity of 515.6 mAh g −1 at a low current density of 0.2 A g −1…

Design, synthesis and application of benzene bioisosteres have attracted a lot of attention in the past 20 years. Recently, bicyclo[2.1.1]hexanes have emerged as highly attractive bioisosteres for ortho- and meta-substituted benzenes. Herein we report a mild, scalable and transition-metal-free protocol for the construction of highly substituted bicyclo[2.1.1]hexan-2-ones through Lewis acid catalyzed (3+2)-cycloaddition of bicyclo[1.1.0]-butane ketones with disubstituted ketenes. The reaction shows high functional group tolerance as documented by the successful preparation of various 3-alkyl-3-aryl as well as 3,3-bisalkyl bicyclo[2.1.1]hexan-2-ones (26 examples, up to 89 % yield). Postfunctionalization of the exocyclic ketone moiety is also demonstrated.

Abstract Layered manganese dioxide is a promising cathode candidate for aqueous Zn‐ion batteries. However, the narrow interlayer spacing, inferior intrinsic electronic conductivity and poor structural stability still limit its practical application. Herein, we report a two‐step strategy to incorporate ammonium ions into manganese dioxide (named as AMO) nanosheets as a cathode for boosted Zn ion storage. K+‐intercalated δ‐MnO2 nanosheets (KMO) grown on carbon cloth are chosen as the self‐involved precursor. Of note, ammonium ions could replace K+ ions via a facile hydrothermal reaction to enlarge the lattice space and form hydrogen‐bond networks. Compared with KMO, the structural stability and the ion transfer kinetics of the layered AMO are enhanced. As expected, the obtained AMO cathode exhibits remarkable electrochemical properties in terms of high reversible capacity, decent rate performance and superior cycling stability over 10000 cycles.

Smart fluorescent materials that can respond to environmental stimuli are of great importance in the fields of information encryption and anti-counterfeiting. However, traditional fluorescent materials usually face problems such as lack of tunable fluorescence and insufficient surface-adaptive adhesion, hindering their practical applications. Herein, inspired by the glowing sucker octopus, we present a novel strategy to fabricate a reversible fluorescent eutectogel with high transparency, adhesive and self-healing performance for conformal information encryption and anti-counterfeiting. Using anthracene as luminescent unit, the eutectogel exhibits photoswitchable fluorescence and can therefore be reversibly written/erased with patterns by non-contact stimulation. Additionally, different from mechanically irreversible adhesion via glue, the eutectogel can adhere to various irregular substrates over a wide temperature range (-20 to 65 °C) and conformally deform more than 1000 times without peeling off. Furthermore, by exploiting surface-adaptive adhesion, high transparency and good…

Abstract Rechargeable aqueous Zn‐VO x batteries are attracting attention in large scale energy storage applications. Yet, the sluggish Zn 2+ diffusion kinetics and ambiguous structure–property relationship are always challenging to fulfil the great potential of the batteries. Here we electrodeposit vanadium oxide nanobelts (VO‐E) with highly disordered structure. The electrode achieves high capacities (e.g., ≈5 mAh cm −2 , 516 mAh g −1 ), good rate and cycling performances. Detailed structure analysis indicates VO‐E is composed of integrated amorphous‐crystalline nanoscale domains, forming an efficient heterointerface network in the bulk electrode, which accounts for the good electrochemical properties. Theoretical calculations indicate that the amorphous‐crystalline heterostructure exhibits the favorable cation adsorption and lower ion diffusion energy barriers compared to the amorphous and crystalline counterparts, thus accelerating charge carrier mobility and electrochemical activity of the electrode.

Abstract Designing novel single‐atom catalysts (SACs) supports to modulate the electronic structure is crucial to optimize the catalytic activity, but rather challenging. Herein, a general strategy is proposed to utilize the metalloid properties of supports to trap and stabilize single‐atoms with low‐valence states. A series of single‐atoms supported on the surface of tungsten carbide (M‐WCx, M=Ru, Ir, Pd) are rationally developed through a facile pyrolysis method. Benefiting from the metalloid properties of WCx, the single‐atoms exhibit weak coordination with surface W and C atoms, resulting in the formation of low‐valence active centers similar to metals. The unique metal‐metal interaction effectively stabilizes the low‐valence single atoms on the WCx surface and improves the electronic orbital energy level distribution of the active sites. As expected, the representative Ru‐WCx exhibits superior mass activities of 7.84 and 62.52 A mgRu−1 for the hydrogen oxidation and evolution reactions (HOR/HER), respectively. In‐depth mechanistic analysis demonstrates that an ideal dual‐sites…

Abstract With ever‐increasing pursuit for high‐value output in recycling spent lithium‐ion batteries (LIBs), traditional recycling methods of cathodes tend to be obsolete because of the complicated procedures. Herein, we first upcycle spent polycrystal LiNi 0.88 Co 0.095 Al 0.025 O 2 (S‐NCA) to high value‐added single‐crystalline and Li‐rich cathode materials through a simple but feasible LiOH‐Na 2 SO 4 eutectic molten salt strategy. The in situ X‐ray diffraction technique and a series of paratactic experiments record the evolution process of upcycling and prove that excessive Li occupies the transition metal (TM) layers. Beneficial from the single‐crystalline and Li‐rich nature, the regenerated NCA (R‐NCA) exhibits remarkably enhanced electrochemical performances in terms of long‐term cyclability, high‐rate performance and low polarization. This approach can also be successfully extended to other cathode materials e.g., LiNi x Co y Mn z O 2 (NCM) and mixed spent NCAs with varied degree of Li loss.

Abstract Electrochemical CO2 reduction (CO2R) at low pH is desired for high CO2 utilization; the competing hydrogen evolution reaction (HER) remains a challenge. High alkali cation concentration at a high operating current density has recently been used to promote electrochemical CO2R at low pH. Herein we report an alternative approach to selective CO2R (>70 % Faradaic efficiency for C2+ products, FEC2+) at low pH (pH 2; H3PO4/KH2PO4) and low potassium concentration ([K+]=0.1 M) using organic film‐modified polycrystalline copper (Modified‐Cu). Such an electrode effectively mitigates HER due to attenuated proton transport. Modified‐Cu still achieves high FEC2+ (45 % with Cu foil /55 % with Cu GDE) under 1.0 M H3PO4 (pH≈1) at low [K+] (0.1 M), even at low operating current, conditions where HER can otherwise dominate.

The parasitic side reaction on Zn anode is the key issue which hinders the development of aqueous Zn-based energy storage systems on power-grid applications. Here, a polymer additive (PMCNA) engineered by copolymerizing 2-methacryloyloxyethyl phosphorylcholine (MPC) and N-acryloyl glycinamide (NAGA) was employed to regulate the Zn deposition environment for satisfying side reaction inhibition performance during long-term cycling with high Zn utilization. The PMCNA can preferentially adsorb on Zn metal surface to form a uniform protective layer for effective water molecule repelling and side reaction resistance. In addition, the PMCNA can guide Zn nucleation and deposition along 002 plane for further side reaction and dendrite suppression. Consequently, the PMCNA additive can enable the Zn//Zn battery with an ultrahigh depth of discharge (DOD) of 90.0 % for over 420 h, the Zn//active carbon (AC) capacitor with long cycling lifespan, and the Zn//PANI battery with Zn utilization of 51.3 % at low N/P ratio of 2.6.

Abstract Photocatalytic conversion of low‐concentration CO2 is considered as a promising way to simultaneously mitigate the environmental and energy issues. However, the weak CO2 adsorption and tough CO2 activation process seriously compromise the CO production, due to the chemical inertness of CO2 molecule and the formed fragile metal‐C/O bond. Herein, we designed and fabricated oxygen vacancy contained Co3O4 hollow nanoparticles on ordered macroporous N‐doped carbon framework (Vo−HCo3O4/OMNC) towards photoreduction of low‐concentration CO2. In situ spectra and ab initio molecular dynamics simulations reveal that the constructed oxygen vacancy is able to break the local structural symmetry of Co−O−Co sites. The formation of asymmetric active site switches the CO2 configuration from a single‐site linear model to a multiple‐sites bending one with a highly stable configuration, enhancing the binding and structural polarization of CO2 molecules. As a result, Vo−HCo3O4/OMNC shows unprecedent activity in the photocatalytic conversion of low‐concentration CO2 (10 % CO2/Ar) under…

The oxygen reduction reaction (ORR) on transition single-atom catalysts (SACs) is sustainable in energy-conversion devices. However, the atomically controllable fabrication of single-atom sites and the sluggish kinetics of ORR have remained challenging. Here, we accelerate the kinetics of acid ORR through a direct O-O cleavage pathway through using a bi-functional ligand-assisted strategy to pre-control the distance of hetero-metal atoms. Concretely, the as-synthesized Fe-Zn diatomic pairs on carbon substrates exhibited an outstanding ORR performance with the ultrahigh half-wave potential of 0.86 V vs. RHE in acid electrolyte. Experimental evidence and density functional theory calculations confirmed that the Fe-Zn diatomic pairs with a specific distance range of around 3 Å, which is the key to their ultrahigh activity, average the interaction between hetero-diatomic active sites and oxygen molecules. This work offers new insight into atomically controllable SACs synthesis and addresses the limitations of the ORR dissociative mechanism.

Abstract Superionic solid electrolytes (SEs) are essential for bulk‐type solid‐state battery (SSB) applications. Multicomponent SEs are recently attracting attention for their favorable charge‐transport properties, however a thorough understanding of how configurational entropy (Δ S conf ) affects ionic conductivity is lacking. Here, we successfully synthesized a series of halogen‐rich lithium argyrodites with the general formula Li 5.5 PS 4.5 Cl x Br 1.5‐ x (0≤ x ≤1.5). Using neutron powder diffraction and 31 P magic‐angle spinning nuclear magnetic resonance spectroscopy, the S 2− /Cl − /Br − occupancy on the anion sublattice was quantitatively analyzed. We show that disorder positively affects Li‐ion dynamics, leading to a room‐temperature ionic conductivity of 22.7 mS cm −1 (9.6 mS cm −1 in cold‐pressed state) for Li 5.5 PS 4.5 Cl 0.8 Br 0.7 (Δ S conf =1.98 R ). To the best of our knowledge, this is the first experimental evidence that configurational entropy of the anion sublattice correlates with ion mobility. Our results indicate the possibility of improving ionic conductivity…

Abstract Synthesis of bicyclic scaffolds has attracted tremendous attention because they are playing an important role as saturated bioisosteres of benzenoids in modern drug discovery. Here, we report a BF3‐catalyzed [2π+2σ] cycloaddition of aldehydes with bicyclo[1.1.0]butanes (BCBs) to access polysubstituted 2‐oxabicyclo[2.1.1]hexanes. A new kind of BCB containing an acyl pyrazole group was invented, which not only significantly facilitates the reactions, but can also serve as a handle for diverse downstream transformations. Furthermore, aryl and vinyl epoxides can also be utilized as substrates which undergo cycloaddition with BCBs after in situ rearrangement to aldehydes. We anticipate that our results will promote access to challenging sp3‐rich bicyclic frameworks and the exploration of BCB‐based cycloaddition chemistry.

Abstract Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2) into multi‐carbon (C2+) products involving C−C coupling. Herein we report a single‐atomic Bi decorated Cu alloy (denoted as BiCu‐SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu‐SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles‐decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm−2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu‐SAA is found to favor the activation of CO2 and subsequent C−C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity.

Abstract Ammonia borane (AB) is a promising material for chemical H 2 storage owing to its high H 2 density (up to 19.6 wt %). However, the development of an efficient catalyst for driving H 2 evolution through AB hydrolysis remains challenging. Therefore, a visible‐light‐driven strategy for generating H 2 through AB hydrolysis was implemented in this study using Ni−Pt nanoparticles supported on phosphorus‐doped TiO 2 (Ni‐Pt/P‐TiO 2 ) as photocatalysts. Through surface engineering, P‐TiO 2 was prepared by phytic‐acid‐assisted phosphorization and then employed as an ideal support for immobilizing Ni−Pt nanoparticles via a facile co‐reduction strategy. Under visible‐light irradiation at 283 K, Ni 40 Pt 60 /P‐TiO 2 exhibited improved recyclability and a high turnover frequency of 967.8 mol mol Pt −1 min −1 . Characterization experiments and density functional theory calculations indicated that the enhanced performance of Ni 40 Pt 60 /P‐TiO 2 originated from a combination of the Ni−Pt alloying effect, the Mott–Schottky junction at the metal‐semiconductor interface, and strong…

Abstract Synergy engineering is an important way to enhance the kinetic activity of oxygen‐evolution‐reaction (OER) electrocatalysts. Here, we fabricated NiFe amorphous nanoreactor (NiFe‐ANR) oxide as OER electrocatalysts via a mild self‐catalytic reaction. Firstly, the amorphousness helps transform NiFe‐ANR into highly active hydroxyhydroxides, and its many fine‐grain boundaries increase active sites. More importantly, as proved by experiments and finite element analysis, the nanoreactor structure alters the spatial curvature and the mass transfer over the catalyst, thereby enriching OH− in the catalyst surface and inner part. Thus, the catalyst with the structure of amorphous nanoreactors gained excellent activity, far superior to the NiFe catalyst with the structure of crystalline nanoreactor or amorphous non‐nanoreactor. This work provides new insights into the applications and mechanisms of amorphousness and nanoreactors, embodying the “1+1>2” synergy of crystalline state and morphology.

In this work, inspired by the principles of a pressure cooker, we utilized a high-pressure method to address the processing challenges associated with high molecular weight polymers. Through this approach, we successfully dissolved high molecular weight D18 in chloroform at 100 °C within a pressure-tight vial. The increased steam pressure raised the boiling point and dissolving capacity of chloroform, enabling the creation of a hybrid film with superior properties, including more ordered molecular arrangement, increased crystallinity, extended exciton diffusion length, and improved phase morphology. Organic solar cells (OSCs) based on D18 : L8-BO prepared using this high-pressure method achieved an outstanding power conversion efficiency of 19.65 %, setting a new record for binary devices to date. Furthermore, this high-pressure method was successfully applied to fabricate OSCs based on other common systems, leading to significant enhancements in device performance. In summary, this research introduces a universal method for processing high molecular weight D18 materials, ultimately…

Abstract The development of flexible zinc‐air batteries (FZABs) has attracted broad attention in the field of wearable electronic devices. Gel electrolyte is one of the most important components in FZABs, which is urgent to be optimized to match with Zn anode and adapt to severe climates. In this work, a polarized gel electrolyte of polyacrylamide‐sodium citric (PAM‐SC) is designed for FZABs, in which the SC molecules contain large amount of polarized −COO − functional groups. The polarized −COO − groups can form an electrical field between gel electrolyte and Zn anode to suppress Zn dendrite growth. Besides, the −COO − groups in PAM‐SC can fix H 2 O molecules, which prevents water from freezing and evaporating. The polarized PAM‐SC hydrogel delivers a high ionic conductivity of 324.68 mS cm −1 and water retention of 96.85 % after being exposed for 96 h. FZABs with the PAM‐SC gel electrolyte exhibit long cycling life of 700 cycles at −40 °C, showing the application prospect under extreme conditions.

Halide perovskites (HPs) recently have emerged as one class of competitive scintillators for X-ray detection and imaging owing to its high quantum efficiency, short decay time, superior X-ray absorption capacity, low cost, and ease of crystal growth. The tunable structure and versatile chemical compositions of halide perovskites provide distinguishable advantages over traditional inorganic scintillators for optimizing scintillation performance. Since the first observation of the scintillation phenomenon in HPs, substantial efforts have been devoted to expanding the inventory of HP scintillators and regulating material properties. Understanding the relationship between the structure and scintillation properties of HP scintillators is essential for developing materials with improved X-ray detection and imaging capacities. This review summarizes strategies for improving the light yield of HP scintillators and provides a roadmap for improving the X-ray imaging performance. Additionally, methods for controlling the light propagation direction in HP scintillators are highlighted for…

Abstract Nitrate‐containing industrial wastewater poses a serious threat to the global food security and public health safety. As compared to the traditional microbial denitrification, electrocatalytic nitrate reduction shows better sustainability with ultrahigh energy efficiency and the production of high‐value ammonia (NH3). However, nitrate‐containing wastewater from most industrial processes, such as mining, metallurgy, and petrochemical engineering, is generally acidic, which contradicts the typical neutral/alkaline working conditions for both denitrifying bacteria and the state‐of‐the‐art inorganic electrocatalysts, leading to the demand for pre‐neutralization and the problematic hydrogen evaluation reaction (HER) competition and catalyst dissolution. Here, we report a series of Fe2M (M=Fe, Co, Ni, Zn) trinuclear cluster metal–organic frameworks (MOFs) that enable the highly efficient electrocatalytic nitrate reduction to ammonium under strong acidic conditions with excellent stability. In pH=1 electrolyte, the Fe2Co‐MOF demonstrates the NH3 yield rate of 20653.5 μg h−1…

Abstract Rational engineering active sites and vantage defects of catalysts are promising but grand challenging task to enhance photoreduction CO 2 to high value‐added C2 products. In this study, we designed an N,S‐codoped Fe‐based MIL‐88B catalyst with well‐defined bipyramidal hexagonal prism morphology via a facile and effective process, which was synthesized by addition of appropriate 1,2‐benzisothiazolin‐3‐one (BIT) and acetic acid to the reaction solution. Under simulated solar irradiation, the designed catalyst exhibits high C 2 H 4 evolution yield of 17.7 μmol g −1 ⋅h, which has been rarely achieved in photocatalytic CO 2 reduction process. The synergistic effect of Fe‐N coordinated sites and reasonable defects in the N,S‐codoped photocatalyst can accelerate the migration of photogenerated carriers, resulting in high electron density, and this in turn helps to facilitate the formation and dimerization of C−C coupling intermediates for C 2 H 4 effectively.

Developing efficient and stable transition metal oxides catalysts for energy conversion processes such as oxygen evolution reaction and oxygen reduction reaction is one of the key measures to solve the problem of energy shortage. The spin state of transition metal oxides is strongly correlated with their catalytic activities. In an octahedral structure of transition metal oxides, the spin state of active centers could be regulated by adjusting the splitting energy and the electron pairing energy. Regulating spin state of active centers could directly modulate the d orbitals occupancy, which influence the strength of metal-ligand bonds and the adsorption behavior of the intermediates. In this review, we clarified the significance of regulating spin state of the active centers. Subsequently, we discussed several characterization technologies for spin state and some recent strategies to regulate the spin state of the active centers. Finally, we put forward some views on the future research direction of this vital field.

Abstract Highly efficient hydrogen evolution reaction (HER) electrocatalyst will determine the mass distributions of hydrogen‐powered clean technologies, while still faces grand challenges. In this work, a synergistic ligand modulation plus Co doping strategy is applied to 1T−MoS 2 catalyst via CoMo‐metal‐organic frameworks precursors, boosting the HER catalytic activity and durability of 1T−MoS 2 . Confirmed by Cs corrected transmission electron microscope and X‐ray absorption spectroscopy, the polydentate 1,2‐bis(4‐pyridyl)ethane ligand can stably link with two‐dimensional 1T−MoS 2 layers through cobalt sites to expand interlayer spacing of MoS 2 (Co−1T−MoS 2 ‐bpe), which promotes active site exposure, accelerates water dissociation, and optimizes the adsorption and desorption of H in alkaline HER processes. Theoretical calculations indicate the promotions in the electronic structure of 1T−MoS 2 originate in the formation of three‐dimensional metal‐organic constructs by linking π‐conjugated ligand, which weakens the hybridization between Mo‐3d and S‐2p orbitals, and in turn makes…