화학공학소재연구정보센터
Electrochimica Acta, Vol.182, 1153-1158, 2015
PPy wrapped MnO2@C/TiO2 nanowire arrays for electrochemical energy storage
Herein, Polypyrrole was used as the conductive wrapping material electro-deposited on the MnO2 nanoflakes covered on C/TiO2 nanowire arrays to form PPy@MnO2@C/TiO2 double shell/core structured arrays electrode for supercapacitor. Their structure and surface morphology were studied by using X-ray diffraction analysis, scanning electron microscopy and transmission electron microscopy. The results suggest that a thin layer of PPy was successfully wrapped on the surface of MnO2, and the shell/core structure of MnO2@C/TiO2 nanowire arrays was not changed after electro-deposition of PPy. The electrochemical tests indicate that the PPy@MnO2@C/TiO2 double shell/core arrays electrode exhibits high specific capacitance of 715 F g(-1) at a charge/discharge current density of 1 A g(-1) and improved specific capacitance retention to 84.0% after 1000 cycles. These results show that the unique three dimensional (3D) double shell/core structured electrode holds promise for high-performance energy storage devices. The superior capacitive perfomance may due to the unique 3D C/TiO2 nanowires and the unique double shell/core structures. Firstly, the 3D C/TiO2 nanowire arrays, as excellent platform for loading active materials, can facilitate the permeation of electrolyte. Moreover, the thin layer PPy tightly wrapped on the MnO2 nanoflakes can improve the electrical conductivity of MnO2. Therefore, the PPy@MnO2@C/TiO2 electrode is promising candidate for electrochemical energy applications. (C) 2015 Elsevier Ltd. All rights reserved.