A modified solvothermal synthesis of porous Mn3O4 for supercapacitor with excellent rate capability and long cycle life

Porous Mn3O4 with micro/nano-structure were fabricated by a modified solvothermal approach using hexadecyltrimethylammonium bromide as a surfactant and CH3CH2OH/H2O as a co-solvent, in which H2O derives from the source material crystalline hydrate Mn(CH3COO)(2)center dot 4H(2)O. It is found that a number of micelles form synchronously surrounding the crystalline hydrate with the addition of Mn(CH3COO)(2)center dot 4H(2)O. The Mn3O4 prepared presents a micro/nano-structure self-assembled by two-dimensional lamella structure with a thickness of approximately 100 nm, and a mesoporous with a specific surface area of 138.5 m(2) g(-1) and a total pore volume of 0.273 cm(3) g(-1). The electrochemical performance of the porous Mn3O4 used as a supercapacitor electrode exhibits a relatively high specific capacitance value of 302 F g(-1) at a low current density of 0.5 A g(-1), and a good high-rate dischargeability (246 F g(-1), 81% capacity retention when the current densities are increased by 10 times (5 A g(-1))), as well as good cycling stability (89% retention after 5000th charge/discharge cycles at 5 A g(-1)). (C) 2015 Elsevier B.V. All rights reserved.