Supported molybdenum carbide (yMo 2 C/M41) and Cu-promoted molybdenum carbide, using a mechanical mixing and co-impregnation method (xCuyMo 2 C/M41-M and xCuyMo 2 C/M41-I) on a mesoporous molecular sieve MCM-41, were prepared by temperature-programmed carburization method in a CO/H 2 atmosphere at 1073 K, and their catalytic performances were tested for CO 2 hydrogenation to form methanol. Both catalysts, which were promoted by Cu, exhibited higher catalytic activity. In comparison to 20Cu20Mo 2 C/M41-M, the 20Cu20Mo 2 C/M41-I catalyst exhibited a stronger synergistic effect between Cu and Mo 2 C on the catalyst surface, which resulted in a higher selectivity for methanol in the CO 2 hydrogenation reaction. Under the optimal reaction conditions, the highest selectivity (63%) for methanol was obtained at a CO 2 conversion of 8.8% over the 20Cu20Mo 2 C/M41-I catalyst.

Metal−organic frameworks (MOFs), combining the advantages of heterogeneous and homogeneous components, have been explored as catalytic materials for the CO2 electroreduction reaction (CO2ERR). However, the unmatched metal nodes result in MOFs having lower faradaic efficiencies (FEs) and limited current densities in CO2ERR. Herein, we report a general strategy to promote activities of MOFs via node doping in CO2ERR. With ion exchange, an active tin node was doped into zeolitic imidazolate framework‐8 (ZIF‐8) to facilitate the reduction kinetics of CO2. The divalent Sn2+ node accelerates the formation of formic acid (HCOOH), resulting in the highest HCOOH FE of 74 % and total current density (Jtotal) of 27 mA/cm2 at −1.1 V (vs. reversible hydrogen electrode, RHE) over 0.6 wt% Sn‐doped ZIF‐8 with stable catalytic performance after seven reuse cycles, which is clearly better compared to the catalytic properties of pristine ZIF‐8 (FEHCOOH=0 %, Jtotal=13 mA/cm2). This work opens an avenue for promoting the CO2ERR performance of MOFs by node doping.

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