Li Jie, Zou Yixiao, Li Zhifeng, Fu Shuhan, Lu Yong, Li Shangyi, Zhu Xiaobiao, Zhang Tingting
Department of Environmental Science and Engineering, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.
College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 10029, People's Republic of China.
ACS Appl Mater Interfaces. 2022 Aug 24;14(33):37865-37877. doi: 10.1021/acsami.2c12036. Epub 2022 Aug 15.
The electronic coordination configuration of metal active sites and the reaction mechanism were investigated by constructing homo-diatomic Fe sites for visible-light-assisted heterogeneous peroxymonosulfate (PMS) activation. A novel FeN catalyst was synthesized by selecting uniform pyridinic-N of graphitic carbon nitride (g-CN) as anchoring sites. The results demonstrated that homo-diatomic Fe sites modulated the d-band center and electron delocalization and thus enhanced the PMS activation kinetics (3.58 times vs single-atom Fe catalyst) with of 0.111 min owing to the synergistic effect between adjacent Fe atoms. New Fe-Fe coordination significantly decreased the contribution of the antibonding state in the Fe-O bond due to the coupling of the Fe-3d orbitals, which facilitated the O-O bond cleavage of the Fe-HOO-SO complex with a reduced thermodynamic energy barrier of only -0.29 eV. This work provided comprehensive mechanistic insights into developing homo-diatomic catalysts governed by the coordination configuration and radical pathway for efficient heterogeneous PMS catalysis.
通过构建用于可见光辅助非均相过一硫酸盐（PMS）活化的同核双原子铁位点，研究了金属活性位点的电子配位构型和反应机理。通过选择石墨相氮化碳（g-CN）中均匀的吡啶氮作为锚定位点，合成了一种新型的FeN催化剂。结果表明，同核双原子铁位点调节了d带中心和电子离域，由于相邻铁原子之间的协同作用，从而提高了PMS活化动力学（相对于单原子铁催化剂提高了3.58倍），其表观一级反应速率常数为0.111 min⁻¹。由于Fe-3d轨道的耦合，新的Fe-Fe配位显著降低了Fe-O键中反键态的贡献，这促进了Fe-HOO-SO络合物的O-O键断裂，其热力学能垒仅降低了-0.29 eV。这项工作为开发由配位构型和自由基途径控制的同核双原子催化剂以实现高效非均相PMS催化提供了全面的机理见解。
