Effect of different precursors on electrochemical properties of manganese oxide thin films prepared by SILAR method

Abstract

We report the synthesis of Mn3O4 thin films prepared by Successive Ionic Layer Adsorption and Reaction method by varying three different cationic precursors namely manganese acetate, manganese chloride, and manganese sulfate. The X-ray diffraction pattern confirms the development of tetragonal (Hausmannite) structured Mn3O4. The Field Emission Scanning Electron Microscopy results show the distribution of grains along with spikes, voids and porous morphology with contact angle values 35°, 26° and 29° for acetate, chloride and sulfate precursors, respectively. From Energy Dispersion X-ray Spectroscopy it is confirmed that ‘Mn' and ‘O' elements are present in the prepared Mn3O4 films. Effect of precursors on the electrochemical properties of Mn3O4 thin films has been studied by using different electrochemical characterizations such as Cyclic Voltammetry, Galvanostatic Charge-Discharge and Electrochemical Impedance Spectroscopy measurements in the 1 M Na2SO4 aqueous electrolyte. Electrode A: Mn3O4, C: Mn3O4 and S: Mn3O4 shows specific capacitance 222 F/g, 375 F/g and 248 F/g respectively at 5 mV/s scan rate. The electrode C: Mn3O4 shows maximum energy density and power density is 17 Wh/kg and 999 W/kg respectively at 0.5 mA/cm2 current density. The C: Mn3O4 electrode shows a good electrochemical behavior with cycling stability of 94% retained after 4500 CV cycles.