Hydrogen Aggregation Enhances CO2 Hydrogenation to Methanol Over In2O3-Based Catalysts.

The hydrogen (H) spillover on the catalyst surface is crucial in the CO2 hydrogenation reaction, but its effects on product selectivity have been rarely investigated. Herein, we reveal the H-spillover mediated regulatory role of oxide supports, which changed the CO2 hydrogenation selectivity on In2O3-based catalysts. By replacing the supports from TiO2 to ZrO2, the primary product of CO2 hydrogenation experiences a significant shift from carbon monoxide (95.6%) to methanol (84.2%). In situ characterization and theoretical modeling evidence that the degree of H-spillover influences the distribution of surface hydrogen species on In2O3-based catalysts, affecting the hydrogenation behavior of formate intermediates and the product distribution. The results illustrate the intrinsic relationship between surface hydrogen atom concentration and methanol synthesis rate in catalytic CO2 hydrogenation over In2O3-based catalysts. This provides the potential to design selective catalysts for CO2 hydrogenation by modulating the degree of H-spillover.