Zr as a structural and electronic mediator in Cu-spinel catalysts: Strengthening MSI for CO2 hydrogenation to methanol

Cu/ZnAl 2 O 4 is a promising alternative to conventional Cu/ZnO/Al 2 O 3 (CZA) catalysts because its higher structural stability suppresses sintering-induced deactivation. However, its performance remains limited by weak metal-support interaction (MSI). Here, Zr was incorporated into the ZnAl 2 O 4 support to regulate the interfacial electronic structure and create defect sites. The optimized catalyst, containing 6 wt% Zr in the support and 8 wt% Cu, achieved a methanol space-time yield of 310.61 g MeOH /kg cat /h at 260 °C, 38% higher than that of the Zr-free sample. It also showed much higher Cu-based activity and stability than CZA. Combined characterizations and DFT calculations reveal that Zr strengthens MSI, suppresses Cu sintering, increases surface oxygen vacancies, and enhances Cu + /Cu 0 synergy, thereby promoting the formate pathway and lowering the barrier of the rate-determining step, which leads to improved methanol synthesis performance.