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Hydrogen-bonded organic frameworks (HOFs) are emerging as multifunctional materials with exceptional biocompatibility, abundant active sites, and tunable porosity, which are highly beneficial for advanced wound care. However, a significant challenge involves transforming pristine HOFs powders into lightweight, ultrathin, freestanding membranes compatible with soft biological systems. Herein, the study successfully develops shape-adaptive HOF-based matrix membranes (HMMs) using a polymer-assisted liquid-air interface technique. The HMMs conform seamlessly to tissues of different sizes and shapes, effectively stopping bleeding, and provide high water-vapor permeability. Notably, both in vitro and in vivo studies with mice wound models demonstrated that these tissue-conformable HMMs significantly accelerate wound healing by modulating the inflammatory environment of the injured tissue and promoting rapid re-epithelialization. Furthermore, RNA-seq analysis and mechanistic studies revealed that HMMs effectively reduce inflammation and facilitate the tissue transition from the proliferative stage to the remodeling stage of skin development. This work not only opens up new avenues for advanced wound care materials but also establishes a foundation for hybridizing HOFs with polymers for a wide range of potential applications., (© 2024 Wiley‐VCH GmbH.)

The sluggish kinetics for anodic oxygen evolution reaction (OER) and insufficient catalytic performance over the corresponding Ir-based catalysts are still enormous challenges in proton exchange membrane water electrolyzer (PEMWE). Herein, it is reported that KIr 4 O 8 nanowires anode catalyst with more exposed active sites and rich hydroxyl achieves a current density of 1.0 A cm -2 at 1.68 V and possesses excellent catalytic stability with 1230 h in PEMWE. Combining in situ Raman spectroscopy and differential electrochemical mass spectroscopy results, the modified adsorbate evolution mechanism is proposed, wherein the rich hydroxyl in the inherent structure of KIr 4 O 8 nanowires directly participates in the catalytic process for favoring the OER. Density functional theory calculation results further suggest that the enhanced proximity between Ir (d) and O (p) band center in KIr 4 O 8 can strengthen the covalence of Ir-O, facilitate the electron transfer between adsorbents and active sites, and decrease the energy barrier of rate-determining step from OH * to O * during the OER., (© 2024 Wiley‐VCH GmbH.)

Cathodic CO 2 adsorption and activation is essential for high-temperature CO 2 electrolysis in solid oxide electrolysis cells (SOECs). However, the component of oxygen ionic conductor in the cathode displays limited electrocatalytic activity. Herein, stable single Ruthenium (Ru) atoms are anchored on the surface of oxygen ionic conductor (Ce 0.8 Sm 0.2 O 2-δ , SDC) via the strong covalent metal-support interaction, which evidently modifies the electronic structure of SDC surface for favorable oxygen vacancy formation and enhanced CO 2 adsorption and activation, finally evoking the electrocatalytic activity of SDC for high-temperature CO 2 electrolysis. Experimentally, SOEC with the Ru 1 /SDC-La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ cathode exhibits a current density as high as 2.39 A cm -2 at 1.6 V and 800 °C. This work expands the application of single atom catalyst to the high-temperature electrocatalytic reaction in SOEC and provides an efficient strategy to tailor the electronic structure and electrocatalytic activity of SOEC cathode at the atomic scale., (© 2023 Wiley-VCH GmbH.)

Electrochemically converting CO 2 to valuable chemicals holds great promise for closing the anthropogenic carbon cycle. Owing to complex reaction pathways and shared rate-determining steps, directing the selectivity of CO 2 /CO electrolysis to a specific multicarbon product is very challenging. We report here a strategy for highly selective production of acetate from CO electrolysis by constructing metal-organic interfaces. We demonstrate that the Cu-organic interfaces constructed by in situ reconstruction of Cu complexes show very impressive acetate selectivity, with a high Faradaic efficiency of 84.2 % and a carbon selectivity of 92.1 % for acetate production, in an alkaline membrane electrode assembly electrolyzer. The maximum acetate partial current density and acetate yield reach as high as 605 mA cm -2 and 63.4 %, respectively. Thorough structural characterizations, control experiments, operando Raman spectroscopy measurements, and density functional theory calculation results indicate that the Cu-organic interface creates a favorable reaction microenvironment that enhances *CO adsorption, lowers the energy barrier for C-C coupling, and facilitates the formation of CH 3 COOH over other multicarbon products, thus rationalizing the selective acetate production., (© 2023 Wiley-VCH GmbH.)

The integration of hydrogen-bonded organic frameworks (HOFs) into electronic devices holds great promise due to their high crystallinity, intrinsic porosity, and easy regeneration. However, despite their potential, the utilization of HOFs in electronic devices remains largely unexplored, primarily due to the challenges associated with fabricating high-quality films. Herein, a controlled synthesis of HOF nanofilms with smooth surface, good crystallinity, and high orientation is achieved using a solution-processed approach. The memristors exhibit outstanding bipolar switching performance with a low set voltage of 0.86 V, excellent retention of 1.64 × 10 4 s, and operational endurance of 60 cycles. Additionally, these robust memristors display remarkable thermal stability, maintaining their performance even at elevated temperatures of up to 200 °C. More strikingly, scratched HOF films can be readily regenerated through a simple solvent rinsing process, enabling their reuse for the fabrication of new memristors, which is difficult to achieve with traditional resistive switching materials. Additionally, a switching mechanism based on the reversible formation and annihilation of conductive filaments is revealed. This work provides novel and invaluable insights that have a significant impact on advancing the widespread adoption of HOFs as active layers in electronic devices., (© 2023 Wiley-VCH GmbH.)

Perovskites exhibit excellent high-temperature oxygen evolution reaction (OER) activities as the anodes of solid oxide electrolysis cells (SOECs). However, the relationship between ion ordering and OER performances is rarely investigated. Herein, a series of PrBaCo 2-x Fe x O 5+δ perovskites with tailored ion orderings are constructed. Physicochemical characterizations and density functional theory calculations confirm that the oxygen bulk migration and surface transport capacities as well as the OER activities are promoted by the A-site cation ordering, but weakened by the oxygen vacancy ordering. Hence, SOEC with the A-site-ordered and oxygen-vacancy-disordered PrBaCo 2 O 5+δ anode exhibits the highest performance of 3.40 A cm -2 at 800 °C and 2.0 V. This work sheds light on the critical role of ion orderings in the high-temperature OER performance and paves a new way for screening novel anode materials of SOECs., (© 2023 Wiley-VCH GmbH.)

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., (© 2023 Wiley-VCH GmbH.)

CO 2 electrolysis is a promising route for achieving net-zero emission through decarbonization. To realize CO 2 electrolysis toward practical application, beyond catalyst structures, it is also critical to rationally manipulate catalyst microenvironments such as the water at the electrode/electrolyte interface. Here, the role of interfacial water in CO 2 electrolysis over Ni-N-C catalyst modified with different polymers is investigated. Benefiting from a hydrophilic electrode/electrolyte interface, the Ni-N-C catalyst modified with quaternary ammonia poly(N-methyl-piperidine-co-p-terphenyl) shows a Faradaic efficiency of 95% and a partial current density of 665 mA cm -2 for CO production in an alkaline membrane electrode assembly electrolyzer. A scale-up demonstration using a 100 cm 2 electrolyzer achieves a CO production rate of 514 mL min -1 at a current of 80 A. In-situ microscopy and spectroscopy measurements indicate that the hydrophilic interface significantly promotes the formation of the *COOH intermediate, rationalizing the high CO 2 electrolysis performance., (© 2023 Wiley-VCH GmbH.)

The design of efficient copper(Cu)-based catalysts is critical for CO 2 electroreduction into multiple carbon products. However, most Cu-based catalysts are favorable for ethylene production while selective production of ethanol with high Faradaic efficiency and current density still remains a great challenge. Herein, we design a carbon-coated CuO x (CuO x @C) catalyst through one-pot pyrolysis of Cu-based metal-organic framework (MOF), which exhibits high selectivity for CO 2 electroreduction to ethanol with Faradaic efficiency of 46 %. Impressively, the partial current density of ethanol reaches 166 mA cm -2 , which is higher than that of most reported catalysts. Operando Raman spectra indicate that the carbon coating can efficiently stabilize Cu + species under CO 2 electroreduction conditions, which promotes the C-C coupling step. Density functional theory (DFT) calculations reveal that the carbon layer can tune the key intermediate *HOCCH goes the hydrogenation pathway toward ethanol production., (© 2022 Wiley-VCH GmbH.)

The electrochemical CO 2 reduction reaction (CO 2 RR) over Cu-based catalysts shows great potential for converting CO 2 into multicarbon (C 2+ ) fuels and chemicals. Herein, we introduce an A 2 M 2 O 7 structure into a Cu-based catalyst through a solid-state reaction synthesis method. The Cu 2 P 2 O 7 catalyst is electrochemically reduced to metallic Cu with a significant structure evolution from grain aggregates to highly porous structure under CO 2 RR conditions. The reconstructed Cu 2 P 2 O 7 catalyst achieves a Faradaic efficiency of 73.6 % for C 2+ products at an applied current density of 350 mA cm -2 , remarkably higher than the CuO counterparts. The reconstructed Cu 2 P 2 O 7 catalyst has a high electrochemically active surface area, abundant defects, and low-coordinated sites. In situ Raman spectroscopy and density functional theory calculations reveal that CO adsorption with bridge and atop configurations is largely improved on Cu with defects and low-coordinated sites, which decreased the energy barrier of the C-C coupling reaction for C 2+ products., (© 2021 Wiley-VCH GmbH.)

Electrochemical CO 2 reduction reaction (CO 2 RR) to multicarbon hydrocarbon and oxygenate (C 2+ ) products with high energy density and wide availability is of great importance, as it provides a promising way to achieve the renewable energy storage and close the carbon cycle. Herein we design a Cu-CuI composite catalyst with abundant Cu 0 /Cu + interfaces by physically mixing Cu nanoparticles and CuI powders. The composite catalyst achieves a remarkable C 2+ partial current density of 591 mA cm -2 at -1.0 V vs. reversible hydrogen electrode in a flow cell, substantially higher than Cu (329 mA cm -2 ) and CuI (96 mA cm -2 ) counterparts. Induced by alkaline electrolyte and applied potential, the Cu-CuI composite catalyst undergoes significant reconstruction under CO 2 RR conditions. The high-rate C 2+ production over Cu-CuI is ascribed to the presence of residual Cu + and adsorbed iodine species which improve CO adsorption and facilitate C-C coupling., (© 2021 Wiley-VCH GmbH.)

Developing copper-free catalysts for CO 2 conversion into hydrocarbons and oxygenates is highly desirable for electrochemical CO 2 reduction reaction (CO 2 RR). Herein, we report a cobalt phthalocyanine (CoPc) and zinc-nitrogen-carbon (Zn-N-C) tandem catalyst for CO 2 RR to CH 4 . This tandem catalyst shows a more than 100 times enhancement of the CH 4 /CO production rate ratio compared with CoPc or Zn-N-C alone. Density functional theory (DFT) calculations and electrochemical CO reduction reaction results suggest that CO 2 is first reduced into CO over CoPc and then CO diffuses onto Zn-N-C for further conversion into CH 4 over Zn-N 4 site, decoupling complicated CO 2 RR pathway on single active site into a two-step tandem reaction. Moreover, mechanistic analysis indicates that CoPc not only generates CO but also enhances the availability of *H over adjacent N sites in Zn-N 4 , which is the key to achieve the high CH 4 production rate and understand the intriguing electrocatalytic behavior which is distinctive to copper-based tandem catalysts., (© 2020 Wiley-VCH GmbH.)

In situ exsolution of metal nanoparticles in perovskite under reducing atmosphere is employed to generate a highly active metal-oxide interface for CO 2 electrolysis in a solid oxide electrolysis cell. Atomic-scale insight is provided into the exsolution of CoFe alloy nanoparticles in La 0.4 Sr 0.6 Co 0.2 Fe 0.7 Mo 0.1 O 3-δ (LSCFM) by in situ scanning transmission electron microscopy (STEM) with energy-dispersive X-ray spectroscopy and DFT calculations. The doped Mo atoms occupy B sites of LSCFM, which increases the segregation energy of Co and Fe ions at B sites and improves the structural stability of LSCFM under a reducing atmosphere. In situ STEM measurements visualized sequential exsolution of Co and Fe ions, formation of CoFe alloy nanoparticles, and reversible exsolution and dissolution of CoFe alloy nanoparticles in LSCFM. The metal-oxide interface improves CO 2 adsorption and activation, showing a higher CO 2 electrolysis performance than the LSCFM counterparts., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)