Zu Xiaolong, Zhao Yuan, Li Xiaodong, Chen Runhua, Shao Weiwei, Li Li, Qiao Panzhe, Yan Wensheng, Pan Yang, Xu Qian, Zhu Junfa, Sun Yongfu, Xie Yi
Hefei National Research Center for Physical Science at Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, P. R. China.
Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201204, P. R. China.
Angew Chem Int Ed Engl. 2023 Jan 2;62(1):e202215247. doi: 10.1002/anie.202215247. Epub 2022 Nov 30.
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 reduction, while the reversible redox-switching metal sites can effectively activate CO 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 /Cu single sites initially accept photoexcited electrons and then donate them to CO molecules, which favors the rate-liming activation into CO , 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 photoreduction to CO with a high rate of 860 μmol g h without any sacrifice reagent or photosensitizer, where both the activity and selectivity outperform previously reported photocatalysts evaluated under similar conditions.
在此，我们首先设计了一种可逆氧化还原切换金属有机框架单胞片材模型，其中丰富的金属单原子位点有利于高选择性的CO还原，而可逆氧化还原切换金属位点可有效激活CO分子。以合成的Cu-MOF单胞片材为例，同步辐射准原位X射线光电子能谱揭示了可逆切换的Cu/Cu单原子位点最初接受光激发电子，然后将其捐赠给CO分子，这有利于限速活化生成CO，原位FTIR光谱和吉布斯自由能计算验证了这一点。结果，Cu-MOF单胞片材在无任何牺牲试剂或光敏剂的情况下，实现了将CO光还原为CO的近100%选择性，高反应速率为860 μmol g⁻¹ h⁻¹，其活性和选择性均优于在类似条件下评估的先前报道的光催化剂。
