▎ 摘　　要

The rational design of highly efficient and durable oxygen reduction reaction (ORR) catalysts is critical for the commercial application of fuel cells. Herein, three-dimensional graphene (3D-G) is synthesized by the template method, which used coal tar pitch as the carbon source and nano MgO as the template. Then, spinel MnCo2O4 is in situ supported on the 3D-G by a facile hydrothermal method, giving MnCo2O4/3D-G. The resultant MnCo2O4/3D-G retains the multilayered mesoporous graphene structure where MnCo2O4 nanoparticles are deposited on the inner walls of pores in the 3D-G. The catalyst MnCo2O4/3D-G shows high electrocatalytic activity with a half-wave potential of 0.81V versus reversible hydrogen electrode, which is clearly superior to those of MnCo2O4/reduced graphene oxide (0.78V), MnCo2O4/carbon nanotubes (0.74V), MnCo2O4/C (0.72V), and 20wt% Pt/C (0.80V). The electron transfer number of MnCo2O4/3D-G indicates a four-electron process of ORR. The durability test demonstrates that the MnCo2O4/3D-G catalyst has a much better durability than 20wt% Pt/C. Our work makes an inspiring strategy to prepare high-performance electrocatalysts for the development of fuel cells.