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Electrochemically converting CO2 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 CO2/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 CH3COOH over other multicarbon products, thus rationalizing the selective acetate production. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (CO2RR) over Cu‐based catalysts shows great potential for converting CO2 into multicarbon (C2+) fuels and chemicals. Herein, we introduce an A2M2O7 structure into a Cu‐based catalyst through a solid‐state reaction synthesis method. The Cu2P2O7 catalyst is electrochemically reduced to metallic Cu with a significant structure evolution from grain aggregates to highly porous structure under CO2RR conditions. The reconstructed Cu2P2O7 catalyst achieves a Faradaic efficiency of 73.6 % for C2+ products at an applied current density of 350 mA cm−2, remarkably higher than the CuO counterparts. The reconstructed Cu2P2O7 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 C2+ products. [ABSTRACT FROM AUTHOR]

[Display omitted] • A defects-rich SnO 2 (e-SnO 2) was obtained from in situ reconstruction of SnSO 4 through an analogous disproportionation process under CO 2 RR condition. • The e-SnO 2 exhibited excellent formate FE over 90% at a wide potential range of ∼ 500 mV and a remarkable formate partial current density of 535 ± 12 mA cm−2, substantially higher than most ever-reported Sn-based catalysts. • DFT calculations revealed that rich defects and surface hydroxyls group facilitate formate production by improving CO 2 adsorption and decreasing the formation energy barrier for the key intermediate *OCOH. Sn-based catalysts have been investigated as efficient catalysts for CO 2 electroreduction toward formate production. However, they still suffer from insufficient current densities and narrow potential windows at high formate Faradaic efficiency. Herein, we developed defect-rich SnO 2 (e-SnO 2) with surface-covered hydroxyls groups in situ derived from SnSO 4 through an analogous disproportionation process. The e-SnO 2 exhibits excellent formate Faradaic efficiency over 90% at a potential range from −0.68 to −1.14 V vs. RHE. The partial current density of formate reaches 535 ± 12 mA cm−2, which is higher than that of most ever-reported Sn-based catalysts. Density functional theory calculations further reveal that the synergistic effects of oxygen vacancies and surface hydroxyls facilitate formate production by improving CO 2 adsorption and balancing the energy barrier for the formation of key intermediate *OCOH. [ABSTRACT FROM AUTHOR]

Abstract: Pt nanoparticles (NPs) have been successfully encapsulated in SBA-15 mesoporous silica support. The silica was firstly functionalized by polyaminoamine (PAMAM) dendrimers with various generations and provided different nanometer space for Pt NPs. The growth of Pt NPs is restricted by the double confinement effect of PAMAM dendrimers and SBA-15 mesopores. The Pt NPs can be precisely controlled to localize inter- or intradendrimeric within SBA-15 tunnels. The different pore structures of Gn-PAMAM-SBA-15 (Gn-PS15) support have great influence on the catalytic performance of the encapsulated Pt NPs. The blocking structure of higher generation Gn-PS15 support debased the catalytic performance and increased the activation energy of reaction between and in a certain degree. [Copyright &y& Elsevier]