Photothermal CO 2 Hydrogenation to Methanol Over Oxygen‐Deficient Molybdenum Suboxide Catalyst

ABSTRACT Photothermal CO 2 hydrogenation to methanol is considered an ideal process for both mitigating CO 2 emissions and producing high‐value chemicals by utilizing sustainable solar energy, in which catalysts combining both CO 2 hydrogenation activity and photothermal conversion features are required. In this study, we demonstrate that oxygen‐deficient molybdenum suboxide catalyst coupled with Pt (Pt/H x MoO 3‐y ) exhibits a high methanol production rate of 1.51 and 1.89 mmol g cat −1 h −1 with CO 2 conversion of 8.6% and 10.9% in the dark and under visible light irradiations, respectively, under relatively mild conditions (200°C, 2.0 MPa), outperforming other oxide analogs. The molybdenum suboxide catalyst provides abundant oxygen vacancies in the presence of H 2 , which promote the activation of CO 2 and modulate the band structure to show quasi‐metallic optical features, thereby expanding the light absorption range and imparting photothermal conversion properties. Based on reaction experiments and kinetic analysis, we demonstrate that the molybdenum suboxide catalyst kinetically promotes the CO 2 hydrogenation by converting incident light into heat. This work provides a fundamental insight for the rational design of oxide‐based catalysts for photothermal CO 2 conversion applications.