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Electrocatalytic CO₂ reduction (ECR) to high value-added chemicals by using renewable electricity presents a promising strategy to realize “carbon neutrality”. However, the ECR system is still limited by its low current density and poor CO₂ utilization efficiency. Herein, by using the confinement effect of covalent organic frameworks (COFs) to confine the in-situ growth of metal nanoclusters (NCs), we develop a series of Cu NCs encapsulated on COF catalysts (Cu-NC@COF) for ECR. Among them, Cu-NC@CuPc-COF as a gas diffusion electrode (GDE) achieves a maximum CO₂-to-CH₄ Faradaic efficiency of 74 ​± ​3% (at −1.0 ​V vs. Reversible Hydrogen Electrode (RHE)) with a current density of 538 ​± ​31 ​mA ​cm⁻² (at −1.2 ​V vs. RHE) in a flow cell, making it one of the best among reported materials. More importantly, the current density is much higher than the relevant industrial current density (200 ​mA ​cm⁻²), indicating the potential for industrial application. This work opens up new possibilities for the design of ECR catalysts that utilize synergistic strategy.

The CO electroreduction reaction (CORR) represents an important piece of the decarbonization puzzle and is heavily inspired by research on the CO₂ electroreduction reaction (CO₂RR). Compared to its parent reaction, CORR circumvents the (bi)carbonate issue that plagues CO₂RR, potentially enabling greater stability and selectivity toward C₂₊ products, particularly oxygenates. Despite its unique potential, CORR still suffers from unsatisfactory performance. In this perspective article, we aim to provide a concise and informative overview of CORR and its close connection with CO₂RR. We start by briefly presenting the two reactions’ similarities and differences, then discussing several catalyst design strategies. This is followed by highlights of the latest results on device integration and engineering. Finally, we offer our thoughts about possible future research opportunities that could render this technology a practical reality.

Two-dimensional conductive metal–organic frameworks (2D-cMOFs) are a class of 2D layered MOFs with excellent electrical conductivity and other electronic properties. In recent years, their porous structure and dense active sites have been widely used in electrocatalysis and electrochemical sensing. The large electron delocalization domains generated by an extended π-conjugated framework through the covalent bonding between metal and organic ligand endow them with unique high conductivity. Yet despite a few promising applications, current research rarely addresses their “structure–property relationship.” This review discusses the rational design of 2D-cMOFs with extraordinary electrochemical performance. We introduce several representative 2D-cMOFs and describe their applications, focusing on electrochemical catalysis and small molecule detection. By correlating the performance of the current materials in these applications and the corresponding mechanisms, we aim to uncover the key structural features that lead to their engineered properties and functions.

Electroreduction of CO₂ into value-added chemicals and fuels utilizing renewable electricity offers a sustainable way to meet the carbon-neutral goal and a viable solution for the storage of intermittent green energy sources. At the core of this technology is the development of electrocatalysts to accelerate the redox kinetics of CO₂ reduction reactions (CO₂RR) toward high targeted-product yield at minimal energy input. This perspective focuses on a unique category of CO₂RR electrocatalysts embodying both inorganic and organic components to synergistically promote the reaction activity, selectivity and stability. First, we summarize recent progress on the design and fabrication of organic/inorganic hybrids CO₂RR electrocatalysts, with special attention to the assembly protocols and structural configurations. We then carry out a comprehensive discussion on the mechanistic understanding of CO₂RR processes tackled jointly by the inorganic and organic phases, with respect to the regulation of mass and charge transport, modification of double-layer configuration, tailoring of intermediates adsorption, and establishment of tandem pathways. At the end, we outline future challenges in the rational design of organic/inorganic hybrids for CO₂RR and further extend the scope to the device level. We hope this work could incentivize more research interests to construct organic/inorganic hybrids for mobilizing electrocatalytic CO₂RR towards industrialization.

Direct electrolytic splitting of seawater for the production of H₂ using ocean energy is a promising technology that can help achieve carbon neutrality. However, owing to the high concentrations of chlorine ions in seawater, the chlorine evolution reaction always competes with the oxygen evolution reaction (OER) at the anode, and chloride corrosion occurs on both the anode and cathode. Thus, effective electrocatalysts with high selectivity toward the OER and excellent resistance to chloride corrosion should be developed. In this critical review, we focus on the prospects of state-of-the-art metal-oxide electrocatalysts, including noble metal oxides, non-noble metal oxides and their compounds, and spinel- and perovskite-type oxides, for seawater splitting. We elucidate their chemical properties, excellent OER selectivity, outstanding anti-chlorine-corrosion performance, and reaction mechanisms. In particular, we review metal oxides that operate at high current densities, near industrial application levels, based on special catalyst design strategies.

Amorphous nanomaterials have emerged as potential candidates for energy storage and conversion owing to their amazing physicochemical properties. Recent studies have proved that the manipulation of amorphous nanomaterials can further enhance electrochemical performance. To date, various feasible strategies have been proposed, of which amorphous/crystalline (a-c) heterointerface engineering is deemed an effective approach to break through the inherent activity limitations of electrode materials. The following review discusses recent research progress on a-c heterointerfaces for enhanced electrochemical processes. The general strategies for synthesizing a-c heterojunctions are first summarized. Subsequently, we highlight various advanced applications of a-c heterointerfaces in the field of electrochemistry, including for supercapacitors, batteries, and electrocatalysts. We also elucidate the synergistic mechanism of the crystalline phase and amorphous phase for electrochemical processes. Lastly, we summarize the challenges, present our personal opinions, and offer a critical perspective on the further development of a-c nanomaterials.

Zn dendrite growth and water-related side reactions have been criticized to hinder actual applications of aqueous Zn-ion batteries. To address these issues, a series of Zn interfacial modifications of building solid/electrolyte interphase (SEI) and nucleation layers have been widely proposed, however, their effectiveness remains debatable. Here, we report a boron nitride (BN)/Nafion layer on the Zn surface to efficiently solve Zn problems through combining the hybrid working mechanisms of SEI and nucleation layers. In our protective layer, Nafion exhibits the SEI mechanism by blocking water from the Zn surface and providing abundant channels for rapid Zn²⁺ transmission, whilst BN nanosheets induce Zn deposition underneath with a preferred (002) orientation. Accordingly, dendrite-free and side-reaction-free Zn electrode with (002) deposition under the protective layer is realized for the first time, as reflected by its high reversibility with average Coulombic efficiency of 99.2% for > 3000 ​h. The protected Zn electrode also shows excellent performance in full cells when coupling with polyaniline cathode under the strict condition of lean electrolyte addition. This work highlights insights for designing highly reversible metal electrodes towards practical applications.

Micro/nano metal–organic frameworks (MOFs) have attracted significant attention in recent years due to their numerous unique properties, with many synthetic methods and strategies being reported for constructing MOFs with specific micro/nano structures. In addition, the design of micro/nano MOFs for energy storage and conversion applications and the study of the structure–activity relationship have also become research hotspots. Herein, a comprehensive overview of the recent progress on micro/nano MOFs is presented. We begin with a brief introduction to the various synthesis methods for controlling the morphology of micro/nano MOFs. Subsequently, the structure-dependent properties of micro/nano MOFs as electrode materials or catalysts in terms of batteries, supercapacitors, and catalysis are discussed. Finally, the remaining challenges and future perspectives in this field are presented. Overall, this review is expected to inspire the design of advanced micro/nano MOFs for efficient energy storage and conversion technologies.

Sn-based materials are promising candidates for lithium storage but suffer generally from huge volume change during the (de)lithiation processes. Sn-organic materials with monodispersed Sn centers surrounded by lithium active ligands can alleviate the volume change of anode materials based on reversible (de)lithiation processes. However, the structural factors governing the kinetics of lithium storage and utilization efficiency of active sites are not well understood to date. Herein, we report three two-dimensional Sn-organic materials with enhanced lithium storage performance by manipulation of π-aromatic conjugation of the ligands. The increasing π-aromatic conjugation plays a key role in promoting efficient lithium storage, and the volume expansion during the (de)lithiation reaction is suppressed in these Sn-organic materials. This work reveals that the π-aromatic conjugation of the ligand is crucial for improving the kinetics of lithium storage and the utilization of active sites in metal-organic materials with minimised volume expansion.

Selective photooxidation of amines to biologically important imines is in great demand for industrial applications. The conversion efficiency and selectivity of the process are strongly dependent on the activation of photocatalytic molecular oxygen (O₂) into reactive oxygen species. Here, we propose the construction of rich interfaces to boost photocatalytic O₂ activation by facilitating the transfer of photocarriers. Taking Bi₃O₄Br/Bi₂O₃ heterojunctions as an example, rich interfaces facilitate electron transfer to adsorbed O₂ for superoxide (${O_2}^{·-}$) generation, thus achieving ≥ 98% conversion efficiency and selectivity for benzylamine and benzylamine derivatives. This study offers a valid method to design advanced photocatalysts for selective oxidation reactions.