• 文献标题:   Coordination Engineering of Defective Cobalt-Nitrogen-Carbon Electrocatalysts with Graphene Quantum Dots for Boosting Oxygen Reduction Reaction
  • 文献类型:   Article
  • 作  者:   GENG D, HUANG YC, YUAN SF, JIANG YY, REN H, ZHANG S, LIU Z, FENG J, WEI T, FAN ZJ
  • 作者关键词:   coordination engineering, electrocatalysi, graphene quantum dot, metalnitrogencarbon, oxygen reduction reaction
  • 出版物名称:   SMALL
  • ISSN:   1613-6810 EI 1613-6829
  • 通讯作者地址:  
  • 被引频次:   4
  • DOI:   10.1002/smll.202207227 EA JAN 2023
  • 出版年:   2023

▎ 摘  要

Developing efficient and robust metal-nitrogen-carbon electrocatalysts for oxygen reduction reaction (ORR) is of great significance for the application of hydrogen-oxygen fuel cells and metal-air batteries. Herein, a coordination engineering strategy is developed to improve the ORR kinetics and stability of cobalt-nitrogen-carbon (Co-N-C) electrocatalysts by grafting the oxygen-rich graphene quantum dots (GQDs) onto the zeolite imidazole frameworks (ZIFs) precursors. The optimized oxygen-rich GQDs-functionalized Co-N-C (G-CoNOC) electrocatalyst demonstrates an increased mass activity, nearly two times higher than that of pristine defective Co-N-C electrocatalyst, and retains a stability of 90.0% after 200 h, even superior to the commercial Pt/C. Comprehensive investigations demonstrate that the GQDs coordination can not only decrease carbon defects of Co-N-C electrocatalysts, improving the electron transfer efficiency and resistance to the destructive free radicals from H2O2, but also optimize the electronic structure of atomic Co active site to achieve a desired adsorption energy of OOH-, leading to enhanced ORR kinetics and stability by promoting further H2O2 reduction, as confirmed by theoretical calculations and experimental results. Such a coordination engineering strategy provides a new perspective for the development of highly active noble-metal-free electrocatalysts for ORR.