Approaching Full-Range Selectivity Control in CO2 Hydrogenation to Methanol and Carbon Monoxide with Catalyst Composition Regulation

CO2 hydrogenation into valuable chemical products has attracted intensive research interest in recent years, with product selectivity control remaining an important topic that requires fine tuning of the catalytic structure and mechanistic understanding. Herein we report our study of anionic phosphorus-regulated indium oxide In2O3 (P-In2O3) nanocatalyst materials for CO2 hydrogenation and achieve nearly full-range selectivity control between methanol and CO products by means of tuning the P content. In situ DRIFTS experiments and XPS characterization reveal the importance of P anion regulation in controlling the CO2 hydrogenation pathways, with an increase in the P content resulting in a decrease in the reducibility of In2O3 that alters CO2 adsorption configuration by blocking and weakening oxygen vacancy (OV) sites for methanol generation and in the meantime creates new sites predominantly active for CO generation. This study demonstrates excellent control of the product selectivity property by regulating the catalyst composition with P anions and provides mechanistic discussions, which offers a new, effective strategy in CO2 hydrogenation catalyst research.