Hierarchical flower-like nanostructures of manganese–cobalt–copper nanoneedles for high performance symmetric supercapacitor
Jyoti Raghav, Tanvi Agarkar, Ashvani Kumar, Soumyendu Roy
Abstract
Hierarchical flower-like structures of nanoneedles of ternary metal oxides comprising of Manganese–Cobalt–Copper (MCC) are synthesized on nickel foam by a simple hydrothermal technique. The synthesis of MCC is done with varying concentrations of manganese and copper, and the products are studied using X-ray photoelectron spectroscopy, X-ray diffraction, and scanning electron microscopy. Electrochemical studies of MCC electrodes are performed using cyclic voltammetry , galvanostatic charge discharge and electrochemical impedance spectroscopy . Ternary metal oxide electrode demonstrates better electrochemical performance in comparison to mono and bimetallic oxide electrodes, which can be attributed to synergistic effects between the metals. Specific capacitance of 1607 F/g at scan rate 5 mV/s is shown by the best performing MCC electrode. The capacitance retention is 98.33% after 2800 charge-discharge cycles. Symmetric device fabricated by the MCC electrode delivers energy density of 37 W h/kg at a power density of 228 W/kg.