Electrodeposition of silver particles from alkaline aqueous solutions and their electrocatalytic activity for the reduction of nitrate, bromate and chlorite ions

Abstract

A pulsed electrochemical method was used for the preparation of silver deposit onto glassy carbon surfaces from an alkaline medium containing ammonia ligand. The morphology of the silver deposit, obtained under pulsed and cyclic conditions was examined and compared using the scanning electron microscopy (SEM) technique. From the experimental evidences, it can be inferred that pulsed method induces a favourable dendritic growth of silver particles, while deposited films obtained under cyclic voltammetry appear formed of globular particles with well regular and defined surface geometry. The electroanalytical performance of the deposited silver, towards the electroreduction of NO 3 −, BrO 3 − and ClO 2 − ions, using cyclic voltammetry and chronoamperometry technique, was evaluated. Interesting analytical results, in terms of sensitivity and temporal reproducibility, in alkaline medium and under constant applied potentials (i.e., −1.45 and −0.6 V vs. SCE), were obtained.