Li Lei, Ying Hanghao, Qiao Panzhe, Liu Wenxiu, Shang Shu, Shao Wei, Wang Hui, Zhang Xiaodong, Xie Yi
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.
Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, P. R. China.
Nano Lett. 2024 Nov 13;24(45):14412-14419. doi: 10.1021/acs.nanolett.4c04304. Epub 2024 Oct 29.
Single-atom catalysts (SACs) that feature uniform metal active sites with symmetry configurations hold great promise in photocatalysis, while their catalytic efficiency is often restricted by the insufficient inherent activity. Drawing inspiration from hard-soft acid-base theory, here we propose that the delocalized electronic state of single-atom centers can be selectively modulated by adjusting their coordination symmetry, thereby optimizing the adsorption and activation of the reactant molecules. By taking ceria-based Ru-SAC (Ru-CeO) as an example, we show that after introducing symmetry breaking, the Ru-CeO with an asymmetric Ru-O configuration (named P-Ru-CeO) exhibits highly delocalized electrons with a soft acidic nature, leading to a much higher photocatalytic performance than for pristine Ru-CeO and CeO counterparts. The corresponding inherent mechanism was systematically investigated by spectroscopy and theoretical studies. This work provides an effective strategy for the design and controllable modulation of atomically dispersed catalysts with symmetry-broken configurations, thereby advancing applications in photocatalysis.
