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

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.