Electronic interaction between transition metal single-atoms and anatase TiO 2 boosts CO 2 photoreduction with H 2 O

• Published in: Energy & environmental science 2022-02, Vol.15 (2), p.601-609
• Main Authors: Lee, Byoung-Hoon, Gong, Eunhee, Kim, Minho, Park, Sunghak, Kim, Hye Rim, Lee, Junho, Jung, Euiyeon, Lee, Chan Woo, Bok, Jinsol, Jung, Yoon, Kim, Young Seong, Lee, Kug-Seung, Cho, Sung-Pyo, Jung, Jin-Woo, Cho, Chang-Hee, Lebègue, Sébastien, Nam, Ki Tae, Kim, Hyungjun, In, Su-Il, Hyeon, Taeghwan
• Format: Article
• Language: English
• ISSN: 1754-5692; 1754-5706
• DOI: 10.1039/D1EE01574E

Single-atom catalysts are playing a pivotal-role in understanding atomic-level photocatalytic processes. However, single-atoms are typically non-uniformly distributed on photocatalyst surfaces, hindering the systematic investigation of structure–property correlation at atomic precision. Herein, by combining material design, spectroscopic analyses, and theoretical studies, we investigate the atomic-level CO 2 photoreduction process on TiO 2 photocatalysts with uniformly stabilized transition metal single-atoms. First, the electronic interaction between single Cu atoms and the surrounding TiO 2 affects the reducibility of the TiO 2 surface, leading to spontaneous O vacancy formation near Cu atoms. The coexistence of Cu atoms and O vacancies cooperatively stabilizes CO 2 intermediates on the TiO 2 surface. Second, our approach allows us to control the spatial distribution of uniform single Cu atoms on TiO 2 , and demonstrate that neighboring Cu atoms simultaneously engage in the interaction with CO 2 intermediates by controlling the charge localization. Optimized Cu 1 /TiO 2 photocatalysts exhibit 66-fold enhancement in CO 2 photoreduction performance compared to the pristine TiO 2 .