Enhancement of dielectric properties by addition of Li–Ti–Si–O nanocomposite to X7R ceramics

BaTiO3-based X7R dielectric materials were obtained by sintering with addition of nano-size 2Li2O–TiO2–SiO2 (LTSO), which was synthesized using a sol–gel method, and showed high activity and great dispersion property. Both the pH value and calcination temperature had significant effects on LTSO particle size. The minimum particle size (∼10 nm) was obtained by performing the sol–gel reaction at a pH of ∼4 followed by further calcination at 550 °C. Moreover, the dielectric property of the ceramics was influenced by the LTSO content and sintering temperature. A high dielectric property (5172) was obtained from BaTiO3-based ceramics with 0.24 mol% LTSO nanocomposite sintered at 1280 °C, which met the requirements of EIA X7R specifications.

► Nano-size Li–Ti–Si–O (LTSO) synthesized via sol–gel method had great dispersity.
► At pH about 4, the particle size of LTSO calcined at 550 °C was minimum (∼10 nm).
► Dielectric property of 5172 was obtained with LTSO satisfying the X7R specification.