Elecrochemical Determination of Ethanol by a Palladium Modified Graphene Nanocomposite Glassy Carbon Electrode

摘要

Pristine palladium nanoparticles were decorated on graphene nanosheets for the development of a low-cost, nonenzymatic ethanol sensor. The nanocomposite was characterized by ultraviolet-visible absorbance spectroscopy, infrared spectroscopy, and field emission scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. Cyclic voltammetry and chronoamperometry were used to quantify ethanol in alkaline media. A graphene palladium nanocomposite-modified glassy carbon electrode provided a detection limit of 2mM with a linear dynamic range of 2-210mM for ethanol determination. The nanocomposite exhibited excellent stability for 100 cyclic voltammetry scans. Ethanol oxidation was performed across a range of temperatures, unlike enzymatic based sensors. Moreover, the catalytic material showed a low activation energy and low onset potentials for the oxidation of ethanol. Interference studies with congeners of ethanol in fermentation chambers showed good selectivity for the analyte. The enhanced catalytic activity for ethanol detection involves the combination of pristine palladium nanoparticles with the enhanced conductivity of graphene.