Atomically dispersed Fe/Co dual site electrocatalysts derived from covalent triazine frameworks for boosting oxygen reduction

Abstract

Single-atom catalysts (SACs), especially transition metal–nitrogen–carbon materials, show high catalytic activity for the oxygen reduction reaction (ORR). Herein, we successfully construct covalent triazine framework (CTF) derived Fe/Co binary metallic SACs by a sequential chemical-doping and complexing adsorption strategy. The obtained atomically dispersed catalyst exhibits an extraordinary ORR performance featuring a half-wave potential of 0.922 V. Meanwhile, the synthesized catalyst shows excellent stability and methanol resistance in both acidic and alkaline media. We further applied the catalyst to Zn–air batteries, showing excellent power density and stability after long-term charge/discharge durability tests. The high ORR activity of the catalyst may result from the synergistic effect of dual metal sites, the high specific surface area and the porous structure. Besides, the doping of Co species provides more defects, which is conducive to the subsequent generation of Fe–N_X species. This work provides valuable insights for the preparation of non-precious metal-based ORR catalysts.