Measuring the Dielectric Constants of Perovskite Nanoparticles in a Polymer Matrix

Barium titanate (BTO) is a perovskite material used in energy storage applications due to its high dielectric constant [1, 2]. Interestingly, Wada et al. found that BTO nanoparticles ranging from 17 to 500nm exhibited a dependence of their dielectric constant on particle size [2]. Particles with sizes over 300 nm exhibited a dielectric constant of 4000, but a sharp increase in dielectric constant to over 15,000 was observed at a BTO size of 70 nm [2]. To investigate the relationship between the particle size and dielectric constant of BTO, we developed an injection molding process to fabricate polymer-matrix nanocomposites containing BTO powders. Here we present our novel fabrication method and the results of our investigation, which was focused on determining the dielectric constants of nanocomposites containing BTO nanoparticles with sizes ranging from 50 to 500 nm. We will discuss our methods of (1) measuring the dielectric constants of nanocomposites and (2) extracting the dielectric constants of the BTO nanoparticles from those measurements and relating them to particle size and volume loading.

[1] Park et al. Journal of Korean Physical Society, Vol. 49 (2006): S680-S683.
[2] Wada et al. Japanese Journal of Applied Physics 42.Part 1, No. 9B (2003): 6188-195.