Nanomaterials (Apr 2023)

Competitive Coordination-Oriented Monodispersed Cobalt Sites on a N-Rich Porous Carbon Microsphere Catalyst for High-Performance Zn−Air Batteries

  • Mengxia Shen,
  • Hao Yang,
  • Qingqing Liu,
  • Qianyu Wang,
  • Jun Liu,
  • Jiale Qi,
  • Xinyu Xu,
  • Jiahua Zhu,
  • Lilong Zhang,
  • Yonghao Ni

DOI
https://doi.org/10.3390/nano13081330
Journal volume & issue
Vol. 13, no. 8
p. 1330

Abstract

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Metal/nitrogen-doped carbon single-atom catalysts (M−N−C SACs) show excellent catalytic performance with a maximum atom utilization and customizable tunable electronic structure. However, precisely modulating the M−Nx coordination in M−N−C SACs remains a grand challenge. Here, we used a N-rich nucleobase coordination self-assembly strategy to precisely regulate the dispersion of metal atoms by controlling the metal ratio. Meanwhile, the elimination of Zn during pyrolysis produced porous carbon microspheres with a specific surface area of up to 1151 m2 g−1, allowing maximum exposure of Co−N4 sites and facilitating charge transport in the oxygen reduction reaction (ORR) process. Thereby, the monodispersed cobalt sites (Co−N4) in N-rich (18.49 at%) porous carbon microspheres (CoSA/N−PCMS) displayed excellent ORR activity under alkaline conditions. Simultaneously, the Zn−air battery (ZAB) assembled with CoSA/N−PCMS outperformed Pt/C+RuO2-based ZABs in terms of power density and capacity, proving that they have good prospects for practical application.

Keywords