Novel nanoporous silver particles for electro-reduction of hydrogen peroxide in alkaline media

Silver nanoparticles (nanoAg) were hydrothermally prepared through the reduction of the complex Ag+-EDTA by polyethylene glycol as the reduction agent and deposited on the titanium surface to form a nanoporous network texture which possesses considerable numbers of active sites. Electrocatalytic activity of the nanoAg electrode towards hydrogen peroxide reduction in 1 NaOH solution was assessed utilizing cyclic voltammetry (CV), linear scanning voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). At the nanoAg electrode, hydrogen peroxide reduction in 1 mol L-1 NaOH took place at a potential of -0.05 V (vs. SCE) and presented considerable large current density of hydrogen peroxide reduction. Cyclic voltammetric responses of the nanoAg electrode showed a fast electro-reduction process of hydrogen peroxide at the initial stage of hydrogen peroxide reduction activation region. Chronoamperometric data on the nanoAg electrode presented stable reduction currents of hydrogen peroxide which exhibited a linear increment with the increasing hydrogen peroxide concentration in the range of 0-0.1 mol L-1. Further, EIS data were obtain at various hydrogen peroxide concentrations and showed significantly low charge transfer resistances for hydrogen peroxide reduction on the nanoAg electrode. Results reveal that the nanoAg electrode of the present investigation is a highly efficient and stable electrocatalyst for hydrogen peroxide reduction in alkaline media. (C) 2011 Elsevier B.V. All rights reserved.