Vertically aligned nanostructured FeOOH@MnO2 core shell electrode with better areal capacitance

Abstract

Present work focuses on hydrothermal preparation of FeOOH@MnO2 core shell as a vertically aligned 1-D nanostructure and improvement in electrochemical charge storage by utilizing MnO2 nanostructure as an active electrode material and vertically aligned FeOOH nanorods for one dimensional electron transfer paths. A FeOOH@MnO2 core shell thin film electrode gives maximum capacitance of 0.252 Fcm−2 for the applied current density of 1 mAcm−2 and maintains 99.5% capacitance retention for 2000 charge discharge cycles at 5 mAcm−2 that attributes to better capacitive charge storage in the material. Assembled solid state symmetric electrochemical capacitor of FeOOH@MnO2 electrode yields maximum of 0.05 mWhcm−2 energy density with power delivery of 1.5 mWcm−2.