Estimation of the point of zero charge of simple and mixed oxides by mass titration

Point of zero charge (pzc) of oxides can be evaluated from the mass titration method described by Schwarz et al. The present paper proposes and validates some simplifications of this method, indicates the capabilities and limits of the simplified method and gives some applications. In particular, the method applies to large solid particles of various oxides. In the case of pure simple oxides, use of electrolyte solutions instead of pure water leads to quite good agreement between experimental results and literature. In the presence of impurities, oxide pzc is modified and the observed shifting can constitute a qualitative analytical way to evaluate the impurity content. The simplified method also applies to mixed oxides.