Fabrication of TiO2@MnO2 nanotube arrays by pulsed electrodeposition and their application for high-performance supercapacitors

The fabrication of TiO2@MnO2 nanotube arrays (NTAs) structure is accomplished via a pulsed electrodeposition technique. The successful preparation of this structure is owing to the high current pulse used, which creates a sufficient nucleation trend on the wall of the entire TiO2 nanotube layer, that results in the continuous deposition of MnO2 along the nanotube walls. The synthesized TiO2@MnO2 NTAs sample is found to exhibit excellent electrochemical behavior with high specific capacitance of 425.0 F g(-1) and areal capacitance of 150.9 mF cm(-2), ranking in the top level ever achieved by a MnO2-TiO2 composite. Furthermore, a symmetric supercapacitor device is assembled using two strips of the TiO2@MnO2 NTAs electrode that yielded energy density as high as 7.4 Wh kg(-1), a much higher value than most of the values reported for symmetric MnO2//MnO2 supercapacitors. The remarkable electrochemical properties of the TiO2@MnO2 NTAs sample make it an attractive candidate for the application of constructing high-performance supercapacitors. (C) 2016 Elsevier Ltd. All rights reserved.