Quasi-Three-Dimensional Cyclotriphosphazene-Based Covalent Organic Framework Nanosheet for Efficient Oxygen Reduction  

作　　者：Jianhong Chang Cuiyan Li Xiaoxia Wang Daohao Li Jie Zhang Xiaoming Yu Hui Li Xiangdong Yao Valentin Valtchev Shilun Qiu Qianrong Fang 

机构地区：[1]State Key Laboratory of Inorganic Synthesis and Preparative Chemistry,Jilin University,Changchun 130012,People’s Republic of China [2]State Key Laboratory of Bio-Fibers and Eco-Textiles,College of Materials Science and Engineering,Qingdao University,Qingdao 266071,People’s Republic of China [3]Qingdao Institute of Bioenergy and Bioprocess Technology,Chinese Academy of Sciences,189 Song Ling Rd,Qingdao 266101,Shandong,People’s Republic of China [4]Laboratoire Catalyse et Spectrochimie,CNRS,ENSICAEN,UNICAEN,Normandie Univ,6 Marechal Juin,14050 Caen,France

出　　处：《Nano-Micro Letters》2023年第9期550-561,共12页纳微快报（英文版）

基　　金：supported by National Key R&D Prog ram of China (2022YFB3704900 and 2021YFF0500500);National Natural Science Foundation of China (22025504, 21621001, and 22105082);the SINOPEC Research Institute of Petroleum Processing;"111"project (BP0719036 and B17020);China Postdoctoral Science Foundation (2020TQ0118 and 2020M681034);the program for JLU Science and Technology Innovative Research Team;the Taishan Scholars Program (No. tsqn202211124)

摘　　要：Metal-free carbon-based materials are considered as promising oxygen reduction reaction(ORR)electrocatalysts for clean energy conversion,and their highly dense and exposed carbon active sites are crucial for efficient ORR.In this work,two unique quasi-three-dimensional cyclotriphosphazene-based covalent organic frameworks(Q3CTP-COFs)and their nanosheets were successfully synthesized and applied as ORR electrocatalysts.The abundant electrophilic structure in Q3CTP-COFs induces a high density of carbon active sites,and the unique bilayer stacking of[6+3]imine-linked backbone facilitates the exposure of active carbon sites and accelerates mass diffusion during ORR.In particular,bulk Q3CTP-COFs can be easily exfoliated into thin COF nanosheets(NSs)due to the weak interlayerπ-πinteractions.Q3CTP-COF NSs exhibit highly efficient ORR catalytic activity(half-wave potential of 0.72 V vs.RHE in alkaline electrolyte),which is one of the best COF-based ORR electrocatalysts reported so far.Furthermore,Q3CTP-COF NSs can serve as a promising cathode for Zn-air batteries(delivered power density of 156 mW cm-2 at 300 mA cm^(-2)).This judicious design and accurate synthesis of such COFs with highly dense and exposed active sites and their nanosheets will promote the development of metal-free carbon-based electrocatalysts.

关 键 词：Covalent organic framework Quasi-three-dimensional structures Oxygen reduction reaction Metal-free electrocatalyst 

分 类 号：O643.36[理学—物理化学] TB383.1[理学—化学] TM911.4[一般工业技术—材料科学与工程]