Phase formation and electrical properties of SBNLT ceramics prepared via combustion technique

Abstract

This report investigates the effect of firing temperatures on the phase formation, microstructure, electrical, and energy storage properties of lead-free Sr 0.3 (Bi 0.7 Na 0.67 Li 0.03 ) 0.5 TiO 3 (SBNLT) ceramics, synthesised by combustion technique. The samples were calcined between 700°C and 900°C for 2 h and sintered between 1100°C and 1200°C for 2 h. The ceramics exhibited coexisting rhombohedral and tetragonal phases, which were confirmed by the Rietveld refinement technique. A morphotropic phase boundary (MPB) of the rhombohedral and tetragonal phases, with a ratio of 49:51, was obtained at the sintering temperature of 1175°C. The highest maximum dielectric constant ( ε max = 4667), polarisation ( P max = 28.80 µC/cm 2 ) and energy density ( W = 0.95 J/cm 3 ), with a breakdown strength of 70 kV/cm, were achieved from the sample sintered at 1175°C.