A highly efficient electrocatalyst for oxygen reduction reaction: Spinel MnCo2O4 nanoparticles supported on three-dimensional Nitrogen-doped graphene material with interconnected hierarchical porous nanostructure

•MnCo2O4/3DNG catalyst was prepared by hydrothermal method using 3DNG as support.•3DNG with hierarchical porous structure possessed enrich the defects and expose more active sites.•MnCo2O4/3DNG with hierarchical porous structure contributed to improve mass transfer.•MnCo2O4/3DNG demonstrated excellent ORR activity and higher durability than 20% Pt/C.