Sulfur adlayer on gold surface for attaining H2O2 reduction in alkaline medium: Catalysis, kinetics, and sensing activities

[Display omitted] •A chemisorbed sulfur adlayer was developed on Au electrode for hydrogen peroxide (HP) reduction in an alkaline medium.•The proposed electrode successfully sorted out the potential dependent breakdown of hydrogen peroxide in Au electrode.•The reduction involves 1st order kinetics in a dual step in the rotational mode, whereas a lone step in the static mode.•The proposed sensor maintained a broad spectrum of linearity (10–2000 µM) with its low limit of detection (6.0 µM). The sensitive detection of hydrogen peroxide (HP) on Au surface is quite challenging owing to the potential dependent decomposition of HP. The current study investigated the development of chemisorbed sulfur adlayer onto the surface of the polycrystalline gold electrode to attain electroreduction of hydrogen peroxide in an alkaline medium using cyclic voltammetry (CV), chronoamperometry, and square wave voltammetry (SWV) measurement techniques. The sulfur adsorbed layer significantly reduces the decomposition of hydrogen peroxide onto the Au (pc) electrode surface allowing the hydrogen peroxide reduction process to proceed. The kinetic diagnosis suggests that the reduction is mass transfer controlled process where electron transfer is the rate determining step in the concerned reduction reaction. The presented electrochemical sensor exhibited high sensitivity and a quick amperometric response to HP in the concentration range of 10–2000 μM, with a detection limit of 6.0 μM.