Adsorption property of citrate dispersant on BaTiO₃ particles in aqueous solution

Abstract

Dispersion behavior of ultra fine BaTiO₃ particles in the aqueous solution of ammonium citrate (NH₄-CA) or citric acid lanthanum chelate (NH₄-La-CA) was investigated. The dispersion property was characterized with sedimentation value. It is easier to obtain well dispersed slurry with NH₄La-CA than NH₄-CA. In an attempt to better understand the role of citric acid radical, simulation of the dispersant adsorption on BaTiO₃ particle was performed with universal force field (UFF). It is demonstrated that the interaction between citric acid radical and BaTiO₃ particle surface is a weak chemical adsorption. Trivalent citric acid radical is adsorbed on BaTiO₃ particle surface with maximal adsorption energy. And, larger molecules of NH₄-La-CA formed by adding La³⁺ lead to better dispersion property than NH₄-CA.

Keywords

citrate dispersant / BaTiO₃ / adsorption

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