Template assisted fabrication of free-standing MnO2 nanotube and nanowire arrays and their application in supercapacitors

Abstract

In this Letter, an innovative technique is reported to control the fabrication of free-standing MnO2 nanotube and nanowire arrays. The synthesis is based on a three-step process, using porous anodic aluminum oxide as a template, and enables the selective fabrication of vertically aligned MnO2 nanotubes or nanowires on large areas. The as-prepared MnO2 nanotube and nanowire arrays are investigated as electrode materials for supercapacitor applications and show a good electrochemical performance with specific capacitances of 210 F g−1 at 1.9 A g−1 and 231 F g−1 at 0.5 A g−1, respectively. The investigation of the rate capability of both structures indicates a superior performance of the nanotube arrays.