Selective Growth of Co-electrodeposited Mn2O3-Au Spherical Composite Network Towards Enhanced Non-enzymatic Hydrogen Peroxide Sensing

Abstract

In the present work, we have fabricated a spherical Mn2O3-Au nanocomposite network on indium tin oxide (ITO) by means of one step co-electrodeposition technique. Upon careful investigation with microscopic and elemental analysis, we observed selective growth of Au cluster wrapped with Mn2O3 spongy mat. The structure and phase of the co-electrodeposited material have been studied with X-Ray Diffraction (XRD), Electron Energy Loss Spectroscopy (EELS), X-ray Photoelectron Spectroscopy (XPS) and Raman spectroscopy. Combined electrochemical and microscopy studies were conducted to understand the formation mechanism of this spherical network. Furthermore, we have investigated the electrochemical property of this elegant nanostructure towards non-enzymatic hydrogen peroxide (H2O2) sensing. We observed an enhanced sensitivity of 39.24μA/mM/cm2 and a low detection limit of 0.34μM towards H2O2 detection exhibited by Mn2O3-Au nanocomposite. The sensitivity value is almost three orders higher than pristine Mn2O3. The performance of our working electrode was also compared with some of the recent reports on enzyme based H2O2 sensors.