Synthesis of Cu@ZnO1-x/Al2O3 catalyst with high-density ZnO1-x-Cu interfacial sites for enhanced CO2 hydrogenation to methanol

The development of catalysts with high-density interfacial sites is crucial for enhancing catalytic performance. However, the efficient construction of interfacial sites remains a significant challenge. In this study, we introduced a ligand-regulated co-precipitation synthesis strategy to fabricate a Cu@ZnO1-x/Al2O3 catalyst. The catalyst possesses high-density partially-reduced ZnO1-x-Cu interfacial sites and exhibits enhanced activity for CO2 hydrogenation to methanol. The methanol space-time yield (STY) of the Cu@ZnO1-x/Al2O3 was 3.8 times higher than that of the commercial Cu/ZnO/Al2O3 after 14 h continuous reaction. Molecular dynamics (MD) simulations and in situ Raman spectroscopy indicated that Cu‒X‒Zn linkage ligands formed in the precursor solution during hydrothermal treatment facilitated zinc-malachite formation during co-precipitation, which promoted Cu-ZnO interface formation during H2 reduction. Moreover, density functional theory (DFT) calculations confirmed partially-reduced ZnO1-x-Cu interfaces were more active via the formate pathway. This work reveals a novel and robust route for designing catalysts with high-density interfacial sites, shedding light on catalyst development.