In situ generated hydrogen- bonding microenvironment in functionalized MOF nanosheets for enhanced CO2 electroreduction

• 成果类型: Article
• 署名作者: Yang, Ge; Huang, Jiajia; Gu, Weizhi; Lin, Zhongyuan; Wang, Qingyu; Kang, Rong; Liu, Jing - Yao; Sun, Zhihu; Zheng, Xusheng; Jiao, Long; Jiang, Hai - Long
• 署名单位: Chinese Academy of Sciences; University of Science & Technology of China, CAS; Chinese Academy of Sciences; University of Science & Technology of China, CAS; Chinese Academy of Sciences; University of Science & Technology of China, CAS; Jilin University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9901
• DOI: 10.1073/pnas.2419434122
• 发表日期: 2025-04-15
• 关键词: metal-organic framework; 2d

摘要

The microenvironment around catalytic sites plays crucial roles in enzymatic catalysis while its precise control in heterogeneous catalysts remains challenging. Herein, the coordinatively unsaturated metal nodes of Hf- based metal- organic framework nanosheets are simultaneously codecorated with catalytically active Co(salen) units and adjacent pyridyl- substituted alkyl carboxylic acids via a post modification route. By varying pyridyl- substituted alkyl carboxylic acids, the spatial positioning of the N atom in pyridine group relative to adjacent Co(salen) can be precisely controlled. Notably, the 3- (pyridin- 4- yl)propionic acid, with para- position pyridine N atom, maximally improves the electrocatalytic CO2 reduction performance of Co(salen) unit, far superior to other counterparts. Mechanism investigations reveal that the pyridine unit of 3- (pyridin- 4- yl)propionic acid is optimally positioned relative to Co(salen) and undergoes in situ reduction to pyridinyl radical under working potentials. This greatly facilitates the stabilization of *COOH intermediate via hydrogen- bonding interaction, lowering the formation energy barrier of *COOH and therefore boosting CO2 electroreduction.