Three-dimensional porous electrode based on silver nanowires for hydrogen sulfide detection

Abstract

A new type of 3D material that allows gas circulation through it composed of polyether sponge, silver nanowires and silver dendrites was built. The material was bonded inside a graphite tube. The silver dendrites were electrochemically deposited on the metallic nanowire network during the recirculation of the electrolyte through the electrode. Air containing 0.89 ÷ 100 ppm H2S was circulated through the porous electrode. Subsequently, the electrode was characterized by cyclic voltammetry. It exhibited a linear response for concentrations between 3.6 ÷ 28.5 ppm H2S in air and the detection limit was below 1 ppm. Due to the large electroactive surface and innovative design it was possible to easily obtain sensitivities of 3.9·104 nA/ppmv at concentrations lower than 1 ppm H2S in air.