Cyclic Voltammetric Sensing of Ethanol Oxidation Using Palladium Nanoparticles with Organic Thiol-Ligand

The detection of ethanol concentration is very important for different applications such as food industry, medicine, beverage, traffic safety and other health related analysis in blood, urine, and saliva.  Recently, Pd nanoparticles (PdNP) have been of interest because exhibit interesting properties such as electrocatalytic activity towards alcohols oxidation in alkaline media, more abundant, and lower costs compared to Pt.  In this work, we synthesized palladium nanoparticles with an organic-thiol ligand by chemical reduction method using sodium borohydride as reducing agent. The organic thiol ligands avoid the agglomeration and controlled particle sizes. The electrochemical detection of ethanol in KOH solution with PdNP with the organic thiol ligand on glassy carbon electrodes was done by cyclic voltammetry (CV). The morphology of PdNP nanoparticles with the organic thiol group was studied using SEM, XPS and TEM. The TEM do not demonstrated agglomeration of the nanoparticles and showed a particles size distribution of 2-10 nanometers. XPS spectra confirmed the presence of metallic palladium and sulphur peaks in the nanoparticles. The electrochemical results proved that the palladium nanoparticles with organic-thiol ligand had an excellent electrocatalytic activity for ethanol oxidation in alkaline media. The palladium nanoparticles are a promising material for ethanol sensors.