Approaching full-range selectivity control in CO2 hydrogenation to methanol and carbon monoxide with catalyst composition regulation

Abstract

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 (O_V) 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.