Boosted CO2 electroreduction performance by enhanced oxygen vacancies in Ag-MOF/CuO nanosheets heterostructures for selective C2H4 production

The Cu-based catalyst used for electrochemical CO 2 reduction reaction (CO 2 RR) is a capable approach to reducing greenhouse carbon emissions and producing high value-added multi-carbon (C2 + ) products. Unfortunately, the selectivity of the (C2 + ) products is still quite low. Therefore, it is imperative to develop persuasive electrocatalysts to facilitate the conversion of carbon dioxide into valuable chemical products. Here, we design a CuO Nanosheets catalyst with the phase composition of silver (Ag) and Ag metal–organic framework (Ag-MOF) by using the hydrothermal approach. A maximum ethylene faradaic efficiency (FE) of Ag-MOF/CuO NS is achieved as 45.72 % at −1.1 V (vs RHE), while those CuO NS and Ag/CuO NS show 31 % and 14.24 % respectively. Interestingly, the restructured porous nature of Ag-MOF doped CuO NS electrocatalyst is equipped with a high surface area with strong adsorption capacity of CO 2 and increases the oxygen vacancies abundance with high active sites for selective electrocatalysis activity based on as produced Ag-MOF on CuO surface. This indicates that, in heterostructured catalysts, the coordination between CuO and free carboxyl groups considerably can enhance the dimerization of *CO intermediates and provide a strong coordination environment to the Cu valence state with MOF for the selective electrocatalytic CO 2 reduction. Thereby, the reaction pathway is shifted from two electrons to a multi-electron by constructing the oxygen vacancies for the production of multi-carbon products.