Size and Temperature Dependence of Dielectric Constant of Ultrafine PbTiO 3 Particles

Using sol-gel method, we prepared ferroelectric PbTiO 3 fine particles with particle size covering the range 20-200 nm; the dielectric properties of powder compact were studied in the present work. The room temperature dielectric constant increases with the decrease in particle size and reaches a maximum value at the size of about 40 nm. The temperature dependence of dielectric constant involving the evolution of particle size during the measurement is discussed.