Partic. vol. 24 pp. 69-72 (February 2016)
doi: 10.1016/j.partic.2014.12.005

Zeta potential measurement on lithium lanthanum titanate nanoceramics

Carlos Ricardo Milian Pila^a, Eduardo Pérez Cappe^a, Yodalgis Mosqueda Laffita^a,*, Oswaldo Luiz Alves^b,

yodalgis@imre.oc.uh.cu

Abstract

The zeta potential, isoelectric point, and agglomeration of Li_0.5La_0.5TiO₃ (LLTO) nanoparticles dispersed in aqueous media at different ionic strengths have been studied. The zeta potential was determined from electrophoretic mobility measurements, according to Smoluchowski's equation, for Li_0.5La_0.5TiO₃ suspensions in NaCl and KCl electrolytes with ionic strengths of 1, 10, and 100 mmol/dm3. The isoelectric point (IEP), zeta potential (ζ), and the agglomeration were shown to strongly depend on the ionic strength of the Li_0.5La_0.5TiO₃ aqueous colloidal suspension in both NaCl and KCl electrolytes, which allows the determination of the effects of environmental conditions for Li_0.5La_0.5TiO₃ manipulation in aqueous colloidal systems. The suspensions of Li_0.5La_0.5TiO₃ nanoparticles reach the IEP in the pH range of 3–5. The ζ of Li_0.5La_0.5TiO₃ nanoparticles varied from positive to negative values with a pH increase, which allows for the control of the surface charge depending on the purpose. The pH range of 7–8 and an ionic strength ≤1 mmol/dm³ are recommended as the most suitable conditions for both the LLTO colloidal shaping techniques application and the LLTO-based nanocomposite formation.

Graphical abstract

Keywords

Titanate; Nanoparticles; Zeta potential; Colloidal suspension