Modulating Ti<i>t</i><sub>2g</sub>Orbital Occupancy in a Cu/TiO<sub>2</sub>Composite for Selective Photocatalytic CO<sub>2</sub>Reduction to CO
Kainan Zhu, Qian Zhu, Mengpei Jiang, Yaowen Zhang, Zhiyu Shao, Zhibin Geng, Xiyang Wang, Hui Zeng, Xiaofeng Wu, Wei Zhang, Keke Huang, Shouhua Feng
Abstract
Abstract The electronic structure of composites plays a critical role in photocatalytic conversion, whereas it is challenging to modulate the orbital for an efficient catalyst. Herein, we regulated the t 2g orbital occupancy state of Ti to realize efficient CO 2 conversion by adjusting the amount of photo‐deposited Cu in the Cu/TiO 2 composite. For the optimal sample, considerable electrons transfer from the Cu d orbital to the Ti t 2g orbital, as proven by X‐ray absorption spectroscopy. The Raman spectra results also corroborate the electron enrichment on the Ti t 2g orbital. Further theoretical calculations suggested that the orbital energy of the Ti 3d orbital in TiO 2 is declined, contributing to accepting Cu 3d electrons. As a result, the Cu/TiO 2 composite exhibited an extremely high selectivity of 95.9 % for CO, and the productivity was 15.27 μmol g −1 h −1 , which is almost 6 times that of the original TiO 2 . Our work provides a strategy for designing efficient photocatalysis as a function of orbital regulation.