Fabrication Of Mn,N-Codoped Carbon Electrocatalysts From A Cationic Cd(Ii)-Based Mof Involving Anion-Exchange With Mno4- Anions

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=N-1,N-1,N-4,N-4 -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 degrees 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.