Sea urchin-like Al-doped MnO 2 nanowires with excellent cycling stability for supercapacitor

Abstract

Homogenous Al-doped MnO 2 supercapacitor materials with excellent electrochemical properties are synthesized by employing an one-step hydrothermal method in this study. The optimal sample shows morphologies of sea urchin-like micro-spheres, which consists of uniform nanowires with diameters of approximate 30 nm. The Al-doped MnO 2 has enhanced crystallinity and electrical conductivity than the pure MnO 2 , which is beneficial to the supercapacitive performance. The optimal Al-doped MnO 2 elctrode material exhibits a high specific capacitance of 101 F·g -1 at a high scan rate of 200 mV·s -1 and a remarkable long-term cycling stability of 99.6% capacitance retention over 20,000 charge/discharge at 5 A·g -1 . These results indicate that the sea urchin-like Al-doped MnO 2 nanowires have extensive application prospects in supercapacitors.