Synergizing W/H Co-Doping and Oxygen Vacancy Incorporation in TiO 2 for CO 2 Photoreduction

Abstract Photocatalytic CO2 reduction to carbonaceous fuels is a promising strategy to mitigate massive carbon emissions, yet the highly selective CO2 conversion remains challenging due to the unsatisfactory charge separation and limited active sites of pristine semiconductor photocatalysts. Herein, we report the in situ fabrication of oxygen vacancy rich W/H co-doped rutile TiO2 (W/H-TiO2) via a two-step wet chemical approach for high-efficiency photocatalytic CO2 reduction to CO. The optimized W/H-TiO2 exhibited high activity and selectivity for the photocatalytic reduction of CO2 to CO (57.96 μmol g–1 h–1 and 96.3%), which were significantly higher than those of other TiO2 counterparts. Experimental characterizations and density functional theory (DFT) calculations reveal that the synergistic effect of H/W co-doping accelerates the migration and separation of photogenerated charge carriers and reduces the formation energy barrier for the key *COOH intermediate, thereby markedly boosting the CO2 photoreduction activity and product selectivity of W/H-TiO2. This work establishes a dual-doping-induced oxygen vacancy strategy for electronic structure engineering, providing a new paradigm for the rational design of high-performance TiO2 based photocatalysts toward efficient CO2 photoreduction.