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The efficient ethanol electrosynthesis from CO2 is challenging with low selectivity at high CO2 electrolysis rates, due to the competition with H2 and other reduction products. Copper‐based bimetallic electrocatalysts are potential candidates for the CO2‐to‐ethanol conversion, but the secondary metal has mainly been focused on active components (such as Ag, Sn) for CO2 electroreduction, which also promote selectivity of ethylene or other reduction products rather than ethanol. Limited attention has been given to alkali‐earth metals due to their inherently active chemical property. Herein, we rationally synthesized a (111) facet‐oriented nano Cu2Mg (designated as Cu2Mg(111)) intermetallic compound with high‐density ordered Cu3‐Mg sites. The in situ Raman spectroscopy and density function theory calculations revealed that the Cu3−δ $_{^{\rm{{\rm \delta} }} }$ −‐Mg−δ $_{^{\rm{{\rm \delta} }} }$ + active sites allowed to increase *CO surface coverage, decrease reaction energy for *CO−CO coupling, and stabilize *CHCHOH intermediates, thus promoting the ethanol formation pathway. The Cu2Mg(111) catalyst exhibited a high FEC2H5OH of 76.2±4.8 % at 600 mA⋅cm−2, and a peak value of |jC2H5OH| of 720±34 mA⋅cm−2, almost 4 times of that using conventional Cu2Mg with (311) facets, comparable to the best reported values for the CO2‐to‐ethanol electroreduction. [ABSTRACT FROM AUTHOR]

Halide solid electrolytes (SEs) have attracted significant attention due to their competitive ionic conductivity and good electrochemical stability. Among typical halide SEs (chlorides, bromides, and iodides), substantial efforts have been dedicated to chlorides or bromides, with iodide SEs receiving less attention. Nevertheless, compared with chlorides or bromides, iodides have both a softer Li sublattice and lower reduction limit, which enable iodides to possess potentially high ionic conductivity and intrinsic anti‐reduction stability, respectively. Herein, we report a new series of iodide SEs: LixYI3+x (x=2, 3, 4, or 9). Through synchrotron X‐ray/neutron diffraction characterizations and theoretical calculations, we revealed that the LixYI3+x SEs belong to the high‐symmetry cubic structure, and can accommodate abundant vacancies. By manipulating the defects in the iodide structure, balanced Li‐ion concentration and generated vacancies enables an optimized ionic conductivity of 1.04 × 10−3 S cm−1 at 25 °C for Li4YI7. Additionally, the promising Li‐metal compatibility of Li4YI7 is demonstrated via electrochemical characterizations (particularly all‐solid‐state Li‐S batteries) combined with interface molecular dynamics simulations. Our study on iodide SEs provides deep insights into the relation between high‐symmetry halide structures and ionic conduction, which can inspire future efforts to revitalize halide SEs. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 conversion to formate is a promising approach for reducing CO2 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 CO2 electroreduction to formate. The s‐SnLi electrocatalyst exhibited one of the best CO2‐to‐formate performances, with a partial current density of −1.0 A cm−2 for producing formate and a corresponding Faradaic efficiency of 92 %. Furthermore, Zn–CO2 batteries equipped with the s‐SnLi catalyst displayed one of the highest power densities of 1.24 mW cm−2 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 CO2‐to‐formate electrosynthesis toward potential commercialization. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 conversion to formate is a promising approach for reducing CO2 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 CO2 electroreduction to formate. The s‐SnLi electrocatalyst exhibited one of the best CO2‐to‐formate performances, with a partial current density of −1.0 A cm−2 for producing formate and a corresponding Faradaic efficiency of 92 %. Furthermore, Zn–CO2 batteries equipped with the s‐SnLi catalyst displayed one of the highest power densities of 1.24 mW cm−2 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 CO2‐to‐formate electrosynthesis toward potential commercialization. [ABSTRACT FROM AUTHOR]