Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)A film of niobium oxide was immobilized on a SiO2/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 SiO2/C/Nb2O5 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 (C) 2010 Elsevier B V All rights reserved831241248Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [06/61214-4]