Regulation of Coordinating Anions around Single Co(II) Sites in a Covalent Organic Framework for Boosting CO<sub>2</sub> Photoreduction
Nan Dai, Yunyang Qian, Denan Wang, Jiajia Huang, Xinyu Guan, Zhongyuan Lin, Weijie Yang, Rui Wang, Jier Huang, Shuang‐Quan Zang, Hai‐Long Jiang
Abstract
High Resolution Image Download MS PowerPoint Slide While photocatalytic CO 2 reduction has been intensively investigated, reports on the influence of anions coordinated to catalytic metal sites on CO 2 photoreduction remain limited. Herein, different coordinated anions (F –, Cl –, OAc –, and NO 3 – ) around single Co sites installed on bipyridine-based three-component covalent organic frameworks (COFs) were synthesized, affording TBD-COF-Co-X (X = F, Cl, OAc, and NO 3 ), for photocatalytic CO 2 reduction. Notably, the presence of these coordinated anions on the Co sites significantly influences the photocatalytic performance, where TBD-COF-Co-F exhibits superior activity to its counterparts. Combined experimental and theoretical results indicate that the enhanced activity in TBD-COF-Co-F is attributed to its efficient charge transfer, high CO 2 adsorption capacity, and low energy barrier for CO 2 activation. This study provides a new strategy for boosting COF photocatalysis through coordinated anion regulation around catalytic metal sites.