Facile synthesis of ZnMn2O4 nanosheets via cathodic electrodeposition: characterization and supercapacitor behavior studies

In this work, we report a facile chemical precipitation method to prepare zinc manganite (ZnMn2O4) materials. ZnMn2O4 nanosheets were synthesized through a cathodic electrolytic electrodeposition (ELD), and their application as supercapacitor electrodes were evaluated. The effect of calcining temperature on the nanostructure and morphology of ZnMn2O4 was investigated systematically through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), FTIR spectroscopy, X-ray diffractometery (XRD), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) surface area measurements. Electrochemical properties of the synthesized products as electrodes in a supercapacitor device were studied using cyclic voltammetry (CV), galvanostatic charge/discharge, and electrochemical impedance spectroscopy in aqueous electrolyte. ZnMn2O4 nanosheets exhibiting remarkable electrochemical performance in supercapacitors with specific capacitance (approximate to 457Fg(-1) at 1Ag(-1)), excellent rate capability (67.2% capacity retention at 10Ag(-1)), and good cycling stability (only 92.5% loss after 4000cycles at 3Ag(-1)). All the results demonstrate that the synthesis route is cost-effective, facile, and can development for prepared electrode materials in electrochemical supercapacitors.