Elucidating the structure-activity relationship of the bimetallic Ni-Cu catalysts for CO2 hydrogenation

The conversion of carbon dioxide (CO2) into high-value products plays a critical role in mitigating atmospheric CO2 levels. Recently, low-cost Ni-based catalysts have been garnering attention due to their exceptional hydrogenation ability. This study focuses on the synthesis of Cu-Ni bimetallic catalysts for CO2 hydrogenation and the systematic evaluation of the relationship between structural evolution and catalytic activity. Through investigation of the selectivity regulation of Cu on Ni-based catalysts, it was discovered that the addition of Cu led to a significant shift in catalytic activity and selectivity. Specifically, the Cu addition transitioned the reaction from being CH4-selective to CO-selective. Moreover, the introduction of Cu preferentially generated a Cu-Ni alloy during the reaction, which resulted in a significant number of *CO species with strong adsorption strength at the interface. Consequently, the subsequent hydrogenation of these *CO species was impeded, rendering the catalyst CO-selective.