Fabrication of binder-free Ni-Mn oxalate electrode for supercapacitor application

Abstract

Herein, we have prepared binder-free flexible Ni-Mn oxalate supercapacitor electrode by simple hydrothermal method. The nickel foam as substrate as well as source of Ni was employed to Ni-Mn oxalate nanostructure. The galvanostatic charge-discharge measurements at range of applied current densities exhibit efficient supercapacitor behavior with 86.3% capacity retention till 10,000 charge discharge cycles and 99% Coloumbic efficiency. The cyclic voltammetry curves at different scan rates reveal good rate capability and stability of Ni-Mn oxalate electrode. The electrochemical impedance study with lower resistance and Warburg element demonstrates higher conductivity and rapid electron/ions diffusion rate. Therefore, synergistic effects of binary Ni-Mn as metal oxalates has overall enhanced the electrochemical performance of Ni-Mn oxalate electrode for supercapacitor application.