Niobium oxide dispersed on a carbon-ceramic matrix, SiO2/C/Nb2O5, used as an electrochemical ascorbic acid sensor.

A film of niobium oxide was immobilized on a SiO(2)/C carbon-ceramic matrix (specific surface area 270 m(2)g(-1)) and characterized by N(2) adsorption-desorption isotherms, scanning electron microscopy, X-ray photoelectron spectroscopy and atomic force microscopy. This new carbon-ceramic material, SiO(2)/C/Nb(2)O(5), was used for construction of electrodes, and it shows ability to improve the electron-transfer between the electrode surface and ascorbic acid. The electrocatalytic oxidation of ascorbic acid was made by differential pulse and cyclic voltammetry techniques, making it potentially useful for developing a new ascorbic acid sensor.