Electrochimica Acta, Vol.202, 8-13, 2016
Ti@delta-MnO2 core-shell nanowire arrays as self-supported electrodes of supercapacitors and Li ion batteries
delta-MnO2 is a promissing electrode material of supercapacitors and Li ion batteries (LIBs) owing to its low cost, layer structure and composite valence of Mn. However, the unfavorable electronic conductivity of delta-MnO2 restricts its rate capability in both of the two devices. Herein, a vertically standing Ti nanowire array modified with delta-MnO2 nanoflakes is prepared by a electrodeposition method, and the electrochemical properties of Ti@delta-MnO2 nanowire arrays in supercapacitors and LIBs are investigated. The results show that, the arrays have a capacity of 195 F g(-1) at 1.0 A g(-1) and can cycle more than 10000 rounds at 10 A g(-1) as electrodes of supercapacitors. On the other hand, the arrays behave good rate capability as LIB cathodes, which can release a capacity of 70 mAh g(-1) at 10C rate charge/discharge. We suggest that, the good electronic conductivity owing to the core-shell structure and the facilitated mass transport supplied by the array architecture are responsible for the enhanced rate performances in the two devices. (C) 2016 Elsevier Ltd. All rights reserved.
Keywords:titanium nanowire arrays;delta type manganese dioxide;lithium ion batteries;supercapacitors