Etude de l'influence de l'ionicité du milieu réactionnel sur les propriétés texturales de gels d'oxyde de titane

A systematic study has been made of the influence of two factors on the synthesis of titanium dioxide gels: (i) the acidity of the reaction medium and (ii) the presence of a solvent. This study demonstrates that, in an aqueous acid medium, the development of textural properties is related to the concentration of free hydrogen ions. The presence in an acid reaction medium of a solvent, such as butanol or benzene, of low dielectric constant, inhibits the development of the structural properties by lowering the ionic dissociation of the acid. Our results provide an explanation for the apparently divergent measurements in the literature.