Large area synthesis of well-dispersed β-MnO2 nanorods and their electrochemical supercapacitive performances

Abstract

Highly dispersed β-MnO2 nanorods are prepared by a simple one-step hydrothermal synthesis method. The structure and morphology of the β-MnO2 nanorods are investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The supercapacitive performances for the electrode made of β-MnO2 nanorods are investigated by cyclic voltammetry (CV) and galvanostatic charging-discharging (GCD). The SEM and TEM results show that these β-MnO2 nanorods have homogeneous 1-D nanostructures in diameter of about 55nm and length of about 500nm. When evaluated for supercapacitor electrode, a relatively high specific capacitance of 247.2 F/g is obtained at current density of 1 A/g in 1mol/L KOH aqueous solution. And desirable rate performance and good cycling stability are also demonstrated for the well-dispersed β-MnO2 nanorods.