Enhanced Adsorption and Dissociation of H<sub>2</sub>O Facilitates Photocatalytic CO<sub>2</sub> Reduction on Defective BiSbO<sub>4</sub>
Peng Chen, Yun Wang, Jiazhen Liao, Yi Liang, Qingqing Ye, Yi Wang, Zhongwei Jiang, Chunhui Shan, Wendong Zhang, Fan Dong
Abstract
The dissociation of H 2 O molecules plays an important role in producing protons for promoting hydrogenation reduction of CO 2 . Therefore, developing excellent photocatalysts to promote the dissociation of H 2 O molecules and reveal the effect mechanism is the key research direction to enhance CO 2 reduction efficiency. In this work, we synthesized BiSbO 4 with oxygen vacancies (OVs) to investigate the photocatalytic mechanism of CO 2 conversion and H 2 O dissociation. Experimental results indicate that the introduction of OVs into BiSbO 4 can enhance the absorption capacity of light, narrowing band gaps and impeding the recombination of photogenerated carriers. Importantly, the existence of OVs in BiSbO 4 can promote the adsorption and activation of H 2 O molecules via the stronger covalent interaction, which facilitates the dissociation of H 2 O molecules to generate more protons and lowers the energy barriers of • COOH to improve the efficiency of CO 2 reduction. This study reinforces our understanding of the principle of photocatalytic CO 2 reduction and the important role of H 2 O dissociation in photocatalytic CO 2 conversion.