CO2 hydrogenation to methanol over Cu-CeO2-ZrO2 catalysts: The significant effect of metal-support interaction

CO2 hydrogenation to methanol is an important pathway to achieving carbon neutrality, with metal-support interaction (MSI) being crucial in the design and optimization of catalysts for this process. In this study, Cu-CeO2-ZrO2 catalysts (CuCe + Zr, CuZr + Ce, CeZr + Cu, and CuCeZr) with different interactions between metal Cu and supports were successfully prepared. We mainly address the problem that how the MSI affects the catalytic performance. The CuCeZr prepared by one step solid-phase method shows the optimal catalytic activity and stability for CO2 hydrogenation, even better than the benchmark commercial Cu-ZnO-Al2O3 catalyst for syngas to methanol. Based on the investigation of the structure-performance relationship of catalysts, we propose that the excellent catalytic activity of CuCeZr is mainly determined by its largest surface area of metallic Cu (S-Cu) and the most amount of Cu species at Cu-support interface, both resulting from the strongest MSI between metallic Cu and CeO2-ZrO2 support. Furthermore, in situ DRIFTS showed that the strong SMI in CuCeZr promotes the formation of formate and its rapid transfer to methoxy, thereby efficiently producing methanol. This work reveals the intrinsic active sites of Cu-CeO2-ZrO2 catalysts from a MSI perspective, providing useful insights for researchers to design highly efficient Cu-based catalysts.