Dynamic Al Migration in Situ Constructs Triple-Active Al–OH/Oxygen Vacancy/CoIn2 Interfaces for Boosting CO2 Hydrogenation to Methanol

Abstract Developing non-noble metal catalysts for CO2 hydrogenation to methanol is challenging. Herein, we report a CoIn2/Al2O3/In2O3 catalyst that achieves a methanol space–time yield (STYMeOH) of 1.08 gMeOH·gcat–1·h–1 at 5 MPa. Under the same experimental conditions as noble metal catalysts, it reaches a STYMeOH of 0.83 gMeOH·gcat–1·h–1, demonstrating performance comparable to that of noble metal systems. The catalyst also exhibits excellent stability, with continuous operation over 100 h, highlighting its practical applicability. Mechanistically, we uncover a dynamic Al migration-induced interfacial reconstruction during reduction: Al originally doped in the In2O3 lattice migrates to the surface, simultaneously generating abundant oxygen vacancies (Odefect, 75.8%) for CO2 activation, forming unique Al–OH weak basic sites that stabilize the critical HCO3* intermediate and promoting highly dispersed CoIn2 alloy for efficient H2 dissociation. In situ DRIFTS reveals a distinct formate pathway (CO2 → HCO3* → HCOO* → H3CO* → CH3OH) enabled by this triple synergy. The combination of earth-abundant components, scalable synthesis, and excellent performance makes this catalyst a promising industrial alternative to noble metal systems.