Catalysis of semiconductor nanoparticles towards electro-oxidation of ascorbic acid

Abstract

Nano-materials show great electrocatalysis on redox reaction, e.g. metal nano-particles and carbon nano-tube. The electrocatalytic activity of semiconductor nano-particles, however, has not been reported although semiconductor was widely used as an electrode substrate for a variety of applications. In this work, we demonstrated a remarkable catalysis on electro-oxidation of ascorbic acid on indium tin oxide nano-particles (ITO NPs)-modified electrode. It was found that the oxidation potential of ascorbic acid decreased by ∼800 mV, compared with that on sputtered ITO film electrode. Coupling with X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) emission studies, the catalytic effect can be deduced to relate with the existence of oxygen vacancy defects in In2O3 crystals, one of the components of ITO. The findings could shed light on fabricating novel electrochemical device for biosensing in future work.