Reversible Switching Cu<sup>II</sup>/Cu<sup>I</sup> Single Sites Catalyze High‐rate and Selective CO<sub>2</sub> Photoreduction
Xiaolong Zu, Yuan Zhao, Xiaodong Li, Runhua Chen, Weiwei Shao, Li Li, Panzhe Qiao, Wensheng Yan, Yang Pan, Qian Xu, Junfa Zhu, Yongfu Sun, Yi Xie
Abstract
Abstract Herein, we first design a model of reversible redox‐switching metal–organic framework single‐unit‐cell sheets, where the abundant metal single sites benefit for highly selective CO 2 reduction, while the reversible redox‐switching metal sites can effectively activate CO 2 molecules. Taking the synthetic Cu‐MOF single‐unit‐cell sheets as an example, synchrotron‐radiation quasi in situ X‐ray photoelectron spectra unravel the reversible switching Cu II /Cu I single sites initially accept photoexcited electrons and then donate them to CO 2 molecules, which favors the rate‐liming activation into CO 2 δ− , verified by in situ FTIR spectra and Gibbs free energy calculations. As an outcome, Cu‐MOF single‐unit‐cell sheets achieve near 100 % selectivity for CO 2 photoreduction to CO with a high rate of 860 μmol g −1 h −1 without any sacrifice reagent or photosensitizer, where both the activity and selectivity outperform previously reported photocatalysts evaluated under similar conditions.