Electrochemical properties of MnO₂/CNT nanocomposite in neutral aqueous electrolyte as cathode material for asymmetric supercapacitors

Abstract

A MnO2/carbon nanotube (CNT) nanocomposite was synthesised using a simple hydrothermal treatment. The nanocomposite exhibits a CNT core/MnO2 porous sheath hierarchy architecture, which makes it promising as an electrode material for supercapacitors. An asymmetric supercapacitor based on activated carbon (AC) as anode, MnO2/CNT nanocomposite as cathode and 1M Na2SO4 solution as electrolyte was assembled in a Swagelok cell. The full cell exhibits excellent power capability, cycling stability and a high energy density of 23 W h/kg at a power density of 330 W/kg based on the total mass of the active electrode materials. This AC//MnO2/CNT asymmetric supercapacitor is promising for high-power applications due to its high energy density and power density.