Effective Charge Separation in a Dual-Single-Atom Photocatalyst for Sacrificial Agent-Free H<sub>2</sub> Evolution
Mengfang Liang, Xiaodong Shao, Yunhee Cho, Amol R. Jadhav, Yosep Hwang, Jinsun Lee, Min Gyu Kim, Yeseul Hong, Sara Ajmal, D. S. Yee, Trang Thu Tran, Jeongyong Kim, Jeongyong Kim, Viet Q. Bui, Thi H. Ho, Shufang Zhao, Young Dok Kim, Ji‐Hee Kim, Ji‐Hee Kim, Hyoyoung Lee
Abstract
The challenge of achieving efficient photocatalytic H 2 production from water splitting without sacrificial agents remains a significant hurdle. Herein, we demonstrate that the dual doping of Cu/Co single atoms on Li-reduced blue TiO 2 (Cu–Co SA/BTO) can effectively modulate the charge separation of photogenerated carriers during photocatalytic pure water splitting. Remarkably, the H 2 evolution rate of Cu–Co SA/BTO achieves a remarkable value of 1238.15 μmol·g –1 ·h –1, surpassing that of BTO by 11 times. Particularly, femtosecond transient absorption spectroscopy (fs-TA) and differential charge densities reveal that the efficient electron–hole separation originates from the doping of Cu/Co dual-single atoms. The doping of Cu single atoms boosts electron transfer from the TiO 2 conduction band to Cu atoms, while the doping of Co single atoms facilitates photogenerated hole migration to Co single atoms from TiO 2 . This work establishes a promising photocatalyst design strategy for achieving highly efficient H 2 evolution through pure water splitting, marking a significant step toward sustainable and green energy production.