Influence of Barium Dissolution on the Electrokinetic Properties of Colloidal BaTiO3 in an Aqueous Medium

Published

October 1, 2003

Author(s)

S K. Lee, Vincent A. Hackley, U Paik

Abstract

Hystersis in the electrokinetic behavior of hydrothermally synthesized colloidal BaTiO₃ is observed during sequential acid and base titrations. Ba²⁺ dissolved during the acid titration results in a Ba-depleted oxide-rich surface. As the acid treated BaTiO₃ suspension is back titrated to pH 10, dissolved Ba²⁺ is adsorbed and/or heterogeneously precipitated onto the particle surface. The combined effects of dissolution and subsequent adsorption-precipitation result in the observed hystersis of the measured dynamic mobility-pH curves. The changes in surface chemistry reflected in the hysteresis are expected to significantly impact dispersion stability. The electrokinetic behavior of BaTiO₃ was measured also after repeated acid treatment, which resulted in TiO₂-like surface chemistry and removal of essentially all available Ba from the surface layer. Based on our results, a qualitative model is offered to explain the electrokinetics of colloidal BaTiO₃ as a function of pH, solids loading and particle size, and an argument is presented in opposition to BaCO₃ contamination as the primary source of dissolved Ba in aqueous BaTiO₃ suspensions.

Citation

Journal of the American Ceramic Society

Volume

86

Issue

No. 10

Pub Type

Journals

Keywords

aqueous tape casting, barium carbonate, barium titanate, dynamic mobility, electrokinetic potential, titanium oxide

Citation

Lee, S. , Hackley, V. and Paik, U. (2003), Influence of Barium Dissolution on the Electrokinetic Properties of Colloidal BaTiO₃ in an Aqueous Medium, Journal of the American Ceramic Society (Accessed January 17, 2025)