On the Correlation between Group III‐A Elements Doping and Structure Performance of Cu/ZnO/ZrO2 Catalysts System for CO2 Hydrogenation to Methanol

Abstract

AbstractA set of Cu/ZnO/ZrO2 catalysts doped with Group‐IIIA elements (M=B, Al, Ga & In) were synthesized via a facile single‐step evaporation‐induced self‐assembly (EISA) method to tune up the catalyst basicity and modulate the structure to improve the methanol yield in CO2 hydrogenation reaction. To understand the catalyst‘s textural properties and catalytic activity, prepared catalysts were exposed to several in‐situ/ex‐situ characterization techniques like Physisorption & Chemisorption studies, XRD, XPS, TEM, and in‐situ DRIFT. The addition of group IIIA elements has a significant impact on the CO2 conversion and Methanol selectivity via tailoring the important textural properties such as metallic surface area of Cu, reducibility of catalysts, particle size, controlled oxygen vacancy, and basicity of catalyst surface. CZZ doped with Al appeared to be the best catalyst, in this study. The modified Cu‐ZnO interface via density functional theory (DFT) calculations also indicated that the CO2 adsorption energy is found to be highest for CZZAl, which is concomitant with CO2‐TPD analysis results. The lowest to highest CO2 adsorption energy order over the catalyst set follows CZZIn<CZZB<CZZGa<CZZO<CZZAl. Moreover, the surface model of Cu/ZnO after doping each element was also studied to elucidate the elemental promotional effect on CO2 adsorption.