Rechargeable aqueous zinc-ion batteries have offered an alternative for large-scale energy storage owing to their low cost and material abundance. However, developing suitable cathode materials with excellent performance remains great challenges, resulting from the high polarization of zinc ion. In this work, an aqueous zinc-ion battery is designed and constructed based on H V O nanowire cathode, Zn(CF SO ) aqueous electrolyte, and zinc anode, which exhibits the capacity of 423.8 mA h g at 0.1 A g , and excellent cycling stability with a capacity retention of 94.3% over 1000 cycles. The remarkable electrochemical performance is attributed to the layered structure of H V O with large interlayer spacing, which enables the intercalation/de-intercalation of zinc ions with a slight change of the structure. The results demonstrate that exploration of the materials with large interlayer spacing is an effective strategy for improving electrochemical stability of electrodes for aqueous Zn ion batteries.

We report single-atom Cu catalysts dispersed on nitrogen-doped carbon by a nitrogen-coordination strategy. The presence of nitrogen enabled good dispersion and attachment of atomic Cu species on the nitrogen-doped carbon frameworks with Cu−N x configurations. The Cu doping concentrations and Cu−N x configurations were well-tuned by the pyrolysis temperature. At a high Cu concentration of 4.9% mol , the distance between neighboring Cu−N x species was close enough to enable C−C coupling and produce C 2 H 4 . In contrast, at Cu concentrations lower than 2.4% mol , the distance between Cu−N x species was large so that the electrocatalyst favored the formation of CH 4 as C 1 products. Density functional theory calculations further confirmed the capability of producing C 2 H 4 by two CO intermediates binding on two adjacent Cu−N 2 sites, while the isolated Cu−N 4 , the neighboring Cu−N 4 , and the isolated Cu−N 2 sites led to formation of CH 4 . Our work demonstrates a facile approach of tuning active Cu sites for CO 2 electroreduction to different hydrocarbons.

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Monodispersed single metal atoms have been demonstrated with unique potentials for electroreduction of CO2 or CO, while the capability of producing multicarbon (C2+) products is still limited. In this work, we developed a dual metal atomic catalyst with uniform distributions of two adjacent Cu–Cu or Cu–Ni atoms anchored on nitrogen-doped carbon frameworks, featuring distinctive catalytic sites for CO electroreduction. Due to the synergistic effect between adjacent metal sites, the dual Cu–Cu atomic catalyst enables efficient CO electroreduction to C2+ products with an outstanding Faradaic efficiency of ∼91% and a high partial current density over 90 mA·cm–2. In contrast, the dual Cu–Ni atomic catalyst exhibits a remarkably different CO electroreduction selectivity mainly toward CH4. Theoretical calculations suggest that the dual Cu atomic sites facilitate the electroreduction of two CO molecules and subsequent carbon–carbon coupling toward ethylene and acetate, while the replacement of one of the dual Cu atoms with Ni results in too strong CO adsorption, and thus only the single Cu atom functions as the catalytic site for the C1 reduction pathway.

Converting CO2 into valuable chemical products has been intensively explored in recent years. Benefited from the substantial cost reduction of clean electricity, the electrochemical methods have been emerging as a potential means for CO2 conversion and fixation. Direct electrochemical CO2 reduction reaction (CO2RR) with H2O is achieved with continuously improved efficiency, selectivity and stability. In contrast, the coupled CO2RR with small molecules and organic substrates, which can allow to form higher valuable chemicals, is still hindered by the poor selectivity, unclear reaction mechanisms, and suboptimal performances of electrocatalysts. Herein, the development of CO2RR with electrocatalysts and reaction mechanisms is first introduced. Several representative examples are described for emphasizing concepts and methodologies. The research process and reaction mechanisms of the coupled CO2RR are then briefly discussed. Finally, challenges and perspectives in this field are addressed to further inspire the development of the fundamental understanding of reaction mechanisms for coupled CO2RR, as well as the optimization of electrocatalysts, electrolytes, and electrolyzers with high activity and selectivity.

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Electroreduction of CO2 into valuable molecules or fuels is a sustainable pathway for CO2 reduction as well as energy storage. However, the premature development stage of electrocatalysts with high activity, selectivity, and durability still remains a significant bottleneck that hinders this field. One‐dimensional (1D) nanomaterials, including nanorods, nanotubes, nanoribbons, nanowires, and nanofibers, are generally considered as high‐activity and stable electromaterials, due to their unique uniform structures, orientated electronic and mass transport, and rigid tolerance to stress variation. During the past several years, 1D nanomaterials and nanostructures have been extensively studied due to their potentials in serving as CO2 electroreduction catalysts. In this minireview, recent studies and advances in 1D nanomaterials for CO2 eletroreduction are summarized, from the viewpoints of both computational and experimental aspects. Based on the composition, the 1D nanomaterials are studied in four categories, including metals, transition‐metal oxides/nitrides, transition‐metal chalcogenides, and carbon‐based materials. Different parameters in tuning 1D materials are also summarized and discussed, such as the crystal facets, grain boundaries, heteroatoms doping, additives and the electrochemical tuning effects. Finally, the challenges and prospects in this direction will be discussed.

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