Supercapacitive performances of MnO2 nanostructures grown on hierarchical Cu nano leaves via electrodeposition

This report describes the fabrication of hybrid electrode system made up of Fluorine-doped tin oxide (FTO), Copper nano leaves and MnO2 nanocrystals in a layer by layer hierarchy. FTO layer on glass was fabricated using a spray pyrolysis process, over that leaves like copper nanostructures were grown by bulk electrolysis method. MnO2 nanocrystals were further coated over FTO-Cu hybrid pattern using manganese acetate as the precursor through electrodeposition process. Purity, crystal structure analysis, structural morphology of all the layers were performed through XRD, FESEM with EDX, AFM etc. XRD pattern confirms the presence of pure FTO, Cu nanoparticles, and MnO2 nanostructures. FESEM micrographs reveal about the leaves like copper pattern, prism-like FTO and needle-shaped MnO2 particles in nano range. Cyclic voltammetry studies performed using electrochemical workstation exhibit a very high specific capacitance values of 486 & 376.7 F g(-1) for the hybrid electrodes in which MnO2 coating time was set to about 350 s and 250 s respectively. Further, Electrochemical Impedance spectroscopic analysis (EIS) supports the pseudocapacitive nature of the fabricated hybrid electrode with a typical semi-circle like EIS curve in the lower frequency region. (C) 2017 Elsevier Ltd. All rights reserved.