Facile electrochemical synthesis of three dimensional flowerlike gold microstructure for electrochemical oxidation of hydrogen peroxide

In the present work, we report a simple and facile templateless electrodeposition of hierarchical flowerlike gold microstructure which was synthesized by using a chronoamperometric (CA) i-t curve technique at a constant applied potential of E = 0.5 V with respect to sat Ag/AgCl (KCl) on indium tin oxide electrode (ITO) substrate. The surface morphology, elemental composition and the preferred orientation of gold microflowers (AuMFs) were characterized using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analyses. The SEM images of the as-prepared AuMFs resembled nanoflakes which are building block for the formation of a three dimensional hierarchical flower-like morphology. Surface elemental composition and valence state of AuMFs is further examined by X-ray photoelectron spectroscopy (XPS). The electrochemical oxidation behavior of AuMFs was investigated by using Cyclic Voltammetry (CV) and chronoamperometric CA techniques with the H2O2 analyst in 0.1 M phosphate buffer solution (pH 7.4). The AuMFs deposited ITO electrodes exhibited excellent electrocatalytic reactivity towards H2O2 oxidation due to the increase of in adsorption of H2O2 on gold-oxide surfaces and it was enhancing the amperometric sensing of H2O2 in neutral solutions. (C) 2018 Elsevier Ltd. All rights reserved.