Highly efficient and stable photothermal catalytic CO2 hydrogenation to methanol over Ru/In2O3 under atmospheric pressure

Abstract

Photothermal catalytic CO2 hydrogenation to CH3OH with renewable H2 is a promising method to convert solar energy into chemical energy. However, it is still impeded by limited CO2 conversion efficiency and poor CH3OH selectivity under mild conditions. Herein, we report a Ru/In2O3 catalyst for efficient and stable photothermal CH3OH production from CO2 hydrogenation under atmospheric pressure. The Ru/In2O3 catalyst delivers a remarkable solar CH3OH production of 280.4 μmol g-1 h-1, which is ∼50 times higher than that of pure In2O3 under the same conditions and surpasses by far reported In2O3-based photothermal catalysts. Detailed characterizations demonstrate that the synergy of photothermal heating effect and hot-carriers-induced activation of reactants on Ru together with the interaction between Ru and In2O3 enhances the activation of CO2 and H2. Moreover, Ru modulates the electronic structure of In2O3 and promotes the generation of oxygen vacancies, which is favorable for the hydrogenation process to form CH3OH. This work paves a way for the rational design of efficient catalysts for solar CH3OH production from CO2 hydrogenation under mild conditions.