Rational Design for Mn3O4@carbon Foam Nanocomposite with 0D@3D Structure for Boosting Electrochemical Performance

Abstract A rational strategy was developed to prepare a nanocomposite with 0D/3D architecture. The composite containing Mn3O4 nanoparticles (0D) and carbon foam (3D) could be applied as an electrode material for supercapacitor by taking advantage of high conductivity of carbon foam (CF) and high pseudocapacitance of Mn3O4 nanoparticles. CF was prepared by a carbonization method using melamine foam, and then Mn3O4 nanoparticles were combined with carbon foam by a one-step hydrothermal method to prepare Mn3O4@CF nanocomposite. The 0D@3D hierarchical structure of Mn3O4@CF nanocomposite using CF as a 3D growing skeleton prevents agglomeration and increases reactive sites of Mn3O4 nanoparticles. In addition, CF as a conductive skeleton shortens the charge transfer path. The synergistic effect between CF and Mn3O4 improves the electrochemical performance of CF. Three Mn3O4@CF composites were prepared by adjusting the mass of the reactants in the processes of hydrothermal reaction. The Mn3O4 nanoparticles are uniformly grown on the CF surface with a diameter of 18 nm. Mn3O4@CF-2 composite has a specific capacitance of 212.8 F/g at a current density of 1 A/g, which is much higher than that of pristine CF (79.1 F/g) and Mn3O4 (112.7 F/g). The cyclic stability of Mn3O4@CF-2 is retained as 86.1% of initial capacitance after 2000 cycles at the current density of 1 A/g. It proves the feasibility of the as-mentioned strategy and broadens the application of carbon foam in supercapacitor.