Ordered porous Mn3O4@N-doped carbon/graphene hybrids derived from metal-organic frameworks for supercapacitor electrodes

An ordered porous Mn3O4@N-doped carbon/graphene (MCG) composite has been synthesized through a facile carbonization of Mn-based metal-organic frameworks (Mn-MOFs) using the poly(styrene-co-AA) spheres as the template. Because of the periodic arrangement of metal nodes and organic ligands in the Mn-MOFs, the Mn3O4 nanoparticles with an average diameter of 7 nm are uniformly distributed and the carbon is formed in situ in the MCG composite. The MCG exhibits a specific surface area of 326 m(2) g(-1) with a total pore volume of 1.02 cm(3) g(-1), which is much higher than that of the Mn3O4-based composites reported to date. In addition, the MCG displays excellent electrochemical performances in an aqueous 1 M Na2SO4 electrolyte with a maximum specific capacitance of 456 F g(-1) at 1 A g(-1) and 246 F g(-1) at 20 A g(-1). The MCG also owns a good cycling stability with 98.1 % of the initial capacitance remaining after 2000 cycles at 5 A g(-1).