One-step carbonization of ZIF-8 in Mn-containing ambience to prepare Mn, N co-doped porous carbon as efficient oxygen reduction reaction electrocatalyst

摘要

Economical and efficient non-noble metal catalysts should be developed practically, instead of commercial Pt/C for fuel cells. In this paper, manganese, nitrogen co-doped porous carbon (Mn-N-C) was synthesized to catalyze oxygen reduction reaction (ORR) through the one-step carbonization of ZIF-8 in the Mn-containing (MnCl2) atmosphere. During the carbonization process, MnCl2 gas was captured with ZIF-8 and then transformed into uniform Mn-N active sites distributed in the porous carbon materials. The Mn-N-C catalyst exhibited plentiful porous structures, large specific surface areas, high graphitization and conductivity, which contributed to the transfer and transport of charge and exposed more active sites. The Mn-N-C catalyst exhibited superior catalytic ability in alkaline and acidic solutions. Half-wave potential of the Mn-N-C could reach 0.88 and 0.73 V in 0.1 M KOH and 0.5 M H2SO4, respectively. In addition, the Mn-N-C catalyst showed a prominent stability after the stability test of 18,000 s. Excellent electrochemical performance and endurance make the Mn-N-C expect to be an effective ORR catalyst to build high-performance fuel cells. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.