Fabrication of Mn,N‐Codoped Carbon Electrocatalysts from a Cationic Cd(II)‐based MOF Involving Anion‐exchange with MnO₄⁻ Anions

Abstract Mn and N‐codoped carbon materials (Mn−N−C) have recently aroused enormous interest owing to their unique advantages over Fe‐N−C counterparts. Mn−N−C electroactive materials have been conveniently fabricated from a cationic Cd(II)‐based MOF (Cd−TTPBA‐4(TTPBA‐4=N¹,N¹,N⁴,N⁴ ‐tetrakis(4‐(4H‐1,2,4‐triazol‐4‐yl)phenyl)benzene‐1,4‐di‐amine) which can effectively and controllably achieve the Mn‐doping through anion‐exchange between the exterior MnO₄⁻ anions and its exchangeable ClO₄⁻ anions. The anion‐exchanged materials of MnO₄⁻@Cd−TTPBA‐4 were pyrolyzed at 1000 °C followed by acid‐washing and second heat‐treatment to give Mn−N−C electroactive materials with promising oxygen reduction activity. In the alkaline electrolyte, the optimal Mn−N−C material exhibits an outstanding oxygen reduction activity with the onset potential of 0.93 V (vs RHE) and half‐wave potential of 0.82 V (vs RHE), together with a good long‐term stability.