The invention relates to a method for the production of thin films, comprising: preparing a solution containing transition metal oxide precursors, a chelating agent and a polar organic solvent; maintaining the solution under agitation in order to form a sol; and using the sol in the form of the transition metal oxide film. The method is characterised in that the chelating agent is selected from among di- or tri-aliphatic carboxylic acids, or salts or mixtures thereof, and in that the polar organic solvent has a boiling temperature at atmospheric pressure of less than 150DEG C.