Mn3O4 hollow microcubes and solid nanospheres derived from a metal formate framework for electrochemical capacitor applications

Mn3O4 hollow microcubes and solid nanospheres were selectively fabricated from a metal formate framework ([CH3NH3][Mn(HCOO)(3)]) by employing the ion exchange reaction in alkaline solution under different hydrothermal conditions. The relationships between Mn3O4 morphology and reaction molar ratio and reaction time were investigated. When used as the electrode materials for supercapacitors, Mn3O4 hollow microcubes and solid nanospheres had specific capacitances of 176 and 150 F g(-1) respectively at a current density of 0.3 A g(-1) in 1 M Na2SO4. The specific capacitance retentions of the Mn3O4 hollow microcubes and solid nanospheres were 95% and 86% respectively after 8000 chargedischarge cycles at a current density of 2 A g(-1). Electrochemical results show that the Mn3O4 hollow microcubes and solid nanospheres exhibit acceptable specific capacitance and excellent cycling stability.