Structure evolutions with enhanced dielectric permittivity and ferroelectric properties of Ba(1-x)(La, Li)xTiO3 ceramics

Polycrystalline Ba(1-x)(La0.50Li0.50)(x)TiO3 (0 <= x <= 0.12) ceramics are fabricated via the solid-state reaction technique to analyze their structure, excellent dielectric permittivity, and ferro/piezoelectric characteristics systematically. Powder x-ray diffraction has revealed the pure polycrystalline tetragonal symmetry for x <= 0.09 compositions. Rietveld refinement analysis has revealed the structure having a reducing tetragonality with increasing composition. A dense and compact ceramic with many grains having different size distributions has been perceived. The substitution of Li and La ions in BaTiO3 unit cell lattice has increased the ambient temperature dielectric permittivity with reduced loss tangent from similar to 2000, similar to 0.019 (for x = 0) to similar to 5166, similar to 0.002 (for x = 0.09) at 1 MHz frequency. In addition, a high bipolar strain similar to 0.24% for x = 0.03 is obtained. The increase of dielectric permittivity with reduced loss tangent might be applicable for capacitor applications at ambient conditions.

Automated summary

Polycrystalline Ba(1-x)(La0.50Li0.50)(x)TiO3 ceramics were fabricated using solid-state reaction technique, to increase dielectric permittivity and potentially apply in capacitor applications.