Electrooxidation of substoichiometric titanium nitrides, TiN1−x, 0bxb0.5

International audienceWeshow that stable titanium oxynitride, TiN1−xOx,may be easily obtained by aqueous electrochemical oxidation of substoichiometric titanium nitride, TiN1−x, for all compositions x comprised between 0 and 0.5. This happens at lower potentials than oxidation into titanium dioxide. Hence, titanium oxynitride free from TiO2 may be synthesized. A two-stepmechanism is proposed for the complete oxidation of the nitride into dioxide: first, the oxynitride is formed on the electrode surface by oxidation of nitrogen vacancies. Then, once formed, the oxynitride can be fully oxidized, to give the dioxide. Measurements of charges associated to voltammetric peaks corroborate this mechanis