In2O3-CNT catalysts enable >500-hour stable CO2-to-methanol hydrogenation via vacancy stabilization.

Indium oxide (In2O3) is a promising catalyst for carbon dioxide (CO2) hydrogenation to methanol but suffers from rapid deactivation due to localized over-reduction of surface In3+ species into inactive metallic In0 near hydrogen (H2) activation sites. Here, we exploit a proton-electron dual-transfer mechanism through a physically integrated In2O3-carbon nanotube (In2O3-CNT) system, achieving simultaneous enhancement of catalytic performance and durability. The optimal In2O3-CNT system gives the highest methanol production rate of 1250.6 grams kilogramsIn2O3-1 hour-1 at 320°C. Particularly, the hybrid system maintains catalytic stability for >500 hours, representing the highest durability among reported In2O3 catalysts. Mechanistic studies and multiple characterization techniques reveal that the conductive CNT network regulates surface redox dynamics by facilitating electron transfer and redistribution. This process promotes the formation of oxygen vacancies for CO2 activation while preventing localized electron accumulation and In0 segregation. The CNT-mediated redox modulation stabilizes a dynamic InOx surface phase by balancing H2-induced reduction and CO2-driven oxidation, thereby sustaining catalytic activity over extended operation.