La-Doped Cu/ZnO/Al2O3 Catalysts with Cu–Zn Coordination: Boosting CO2 Hydrogenation to Methanol via High-Density Cu–ZnO1–x Interfaces and Cu0/Cu+ Regulation

Cu/ZnO/Al2O3 (CZA) catalyst remains the benchmark for methanol synthesis but suffers from active-site sintering and insufficient CO2 activation. In this study, we proposed a dual strategy to enhance and regulate the active sites of CZA: hydrothermal treatment induces Cu–Zn coordination to create high-density Cu–ZnO1–x interfaces that promote CO2 conversion, while subsequent La doping regulates Cu0/Cu+ species to favor methanol selectivity. As a result, the maximum space-time yield (STY) of methanol over the designed CZA&5%La-LRCP (prepared by the ligand-regulated coprecipitation method) catalyst improved significantly from 283.0 gMeOH·kgcat–1·h–1 for the conventional coprecipitation-prepared CZA to 400.4 gMeOH·kgcat–1·h–1 under the tested conditions, surpassing most literature reports on La-doped Cu-based catalysts. Comprehensive characterizations and kinetic studies revealed that high-density Cu–ZnO1–x interfaces enhance CO2 adsorption and activation, while uniformly distributed electron-enriched Cu0/Cu+ species promote H2 dissociation and facilitate formate formation and transformation, together establishing an efficient pathway for CO2 activation and hydrogenation. This study demonstrates a promising strategy for the rational design of CO2hydrogenation catalysts through the synergistic modulation of interfacial structure and electronic properties.