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

An ordered porous Mn 3 O 4 @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 Mn 3 O 4 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 Mn 3 O 4 -based composites reported to date. In addition, the MCG displays excellent electrochemical performances in an aqueous 1 M Na 2 SO 4 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 .