Exploring carbon-based Cu-ZnO catalyst and substitutes for enhanced selective methanol production from CO₂: An...

Methanol, produced through the hydrogenation of carbon dioxide, is an essential intermediate compound that plays a crucial function in the production of various organic chemicals. Enhancing the design of copper-containing catalysts for the transformation of CO₂ to methanol is a popular strategy in scientific literature, although challenges persist in advancing the efficiency of carbon dioxide transformation and the selectivity of methanol production. This research aims at creating CuZnO-M/rGO (M = Mg, Mn, and Cr) catalysts using an efficient method for selectively converting CO₂ to methanol. By optimizing the operational parameters of this system, methanol productivity and CO₂ conversion efficiency are enhanced. Under optimal conditions, a CO₂ conversion rate of 23.5%, methanol selectivity of 90%, and a space-time yield of 0.47 g_MeOH.g_cat^-1.h^-1 were achieved with the CuZnO-MgO (5)/rGO catalyst. These levels were maintained over a 100-h period, demonstrating the stability of the catalyst system. These findings are highly consistent with the density functional theory (DFT) calculations, revealing that the CuZnO-MgO (5)/rGO catalyst possesses a -0.35 eV adsorption energy for CO₂ and a favorable reaction pathway with the overpotential of 1.16 V towards methanol production emphasizing the high conversion and selectivity obtained.