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Although there are plenty of merits for lithium–sulfur (Li–S) batteries, their undesired shuttle effect and insulated nature are hindering the practical applications. Here, a conductive metal–organic framework (MOF)-modified separator has been designed and fabricated through a facile filtration method to address the issues. Specifically, its intrinsic microporous structure, hydrophilic polar property, and conductive feature could make it easy to contact with and trap polysulfides and boost the kinetics of electrochemical reactions. Both the physical and chemical properties of the as-prepared separator are beneficial to alleviating the shuttle effect and enhancing the rate capability. Accordingly, the electrochemical performance of the battery with a MOF-modified separator was significantly improved.

The electrochemical CO 2 conversion to formate is a promising approach for reducing CO 2 level and obtaining value-added chemicals, but its partial current density is still insufficient to meet the industrial demands. Herein, we developed a surface-lithium-doped tin (s-SnLi) catalyst by controlled electrochemical lithiation. Density functional theory calculations indicated that the Li dopants introduced electron localization and lattice strains on the Sn surface, thus enhancing both activity and selectivity of the CO 2 electroreduction to formate. The s-SnLi electrocatalyst exhibited one of the best CO 2 -to-formate performances, with a partial current density of À1.0 A cm À2 for producing formate and a corresponding Faradaic efficiency of 92 %. Furthermore, Zn-CO 2 batteries equipped with the s-SnLi catalyst displayed one of the highest power densities of 1.24 mW cm À2 and an outstanding stability of > 800 cycles. Our work suggests a promising approach to incorporate electron localization and lattice strain for the catalytic sites to achieve efficient CO 2 -to-formate electrosynthesis toward potential commercialization.

The high‐rate electrochemical CO2 conversion to ethanol with high partial current density is attractive but challenging, which requires competing with other reduction products as well as hydrogen evolution. This work demonstrates the in situ reconstruction of KCuF3 perovskite under CO2 electroreduction conditions to fabricate a surface fluorine‐bonded, single‐potassium‐atom‐modified Cu(111) nanocrystal (K–F–Cu–CO2). Density functional theory calculations reveal that the co‐modification of both F and K atoms on the Cu(111) surface can promote the ethanol pathway via stabilization of the CO bond and selective hydrogenation of the CC bond in the CH2CHO* intermediate, while the single modification of either F or K is less effective. The K–F–Cu–CO2 electrocatalyst exhibits an outstanding CO2‐to‐ethanol partial current density of 423 ± 30 mA cm−2 with the corresponding Faradaic efficiency of 52.9 ± 3.7%, and a high electrochemical stability at large current densities, thus suggesting an attractive means of surface co‐modification of halide anions and alkali‐metal cations on Cu catalysts for high‐rate CO2‐to‐ethanol electrosynthesis.

The photoelectrochemical carbon dioxide reduction reaction (PEC-CO 2 RR) allows us to convert solar power to chemical energy with photosensitive materials. Semiconductor-based, plasmon-assisted, and dye-sensitized systems have been extensively investigated in the PEC-CO 2 RR. Beyond the remarkable progress in materials science, it is expected to realize new systems for satisfying the needs of both research discoveries and industry applications. In this Perspective, we summarize the latest progress in the field of the PEC-CO 2 RR, focusing on enhancing efficiencies via matching photoelectron flux, charge transfer rate, and mass transport rate. Based on the principles for the state-of-the-art PEC-CO 2 RR, new designs of the system engineering strategies on photoelectrode fabrication, reactor design, electrolyte optimization, and membrane selection are proposed to enhance selectivity and stability of the PEC-CO 2 RR.