Nano Convergence (Apr 2022)

Modulating the electrocatalytic activity of N-doped carbon frameworks via coupling with dual metals for Zn–air batteries

  • Jung Hyun Park,
  • Jae-Hoon Shin,
  • Jong-Min Ju,
  • Jun-Hyeong Lee,
  • Chanhee Choi,
  • Yoonhee So,
  • Hyunji Lee,
  • Jong-Ho Kim

DOI
https://doi.org/10.1186/s40580-022-00308-8
Journal volume & issue
Vol. 9, no. 1
pp. 1 – 10

Abstract

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Abstract N-Doped carbon electrocatalysts are a promising alternative to precious metal catalysts to promote oxygen reduction reaction (ORR). However, it remains a challenge to design the desired active sites on carbon skeletons in a controllable manner for ORR. Herein, we developed a facile approach based on oxygen-mediated solvothermal radical reaction (OSRR) for preparation of N-doped carbon electrocatalysts with a pre-designed active site and modulated catalytic activity for ORR. In the OSRR, 2-methylimidazole reacted with Co and Mn salts to form an active site precursor (MnCo-MIm) in N-methyl-2-pyrrolidone (NMP) at room temperature. Then, the reaction temperature increased to 140 °C under an oxygen atmosphere to generate NMP radicals, followed by their polymerization with the pre-formed MnCo-MIm to produce Mn-coupled Co nanoparticle-embedded N-doped carbon framework (MnCo-NCF). The MnCo-NCF showed uniform dispersion of nitrogen atoms and Mn-doped Co nanoparticles on the carbon skeleton with micropores and mesopores. The MnCo-NCF exhibited higher electrocatalytic activity for ORR than did a Co nanoparticle only-incorporated carbon framework due to the improved charge transfer from the Mn-doped Co nanoparticles to the carbon skeleton. In addition, the Zn–air battery assembled with MnCo-NCF had superior performance and durability to the battery using commercial Pt/C. This facile approach can be extended for designing carbon electrocatalysts with desired active sites to promote specific reactions. Graphical Abstract

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