Dielectric and energy storage properties of Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ doped Ba _0.85 Ca _0.15 Zr _0.1 Ti _0.9 O ₃ lead-free glass-ceramics

Abstract

A sol–gel method is employed for preparing high quality lead-free glass-ceramic samples (1 − x )BCZT- x BBS—incorporating Ba 0.85 Ca 0.15 Zr 0.1 Ti 0.9 O 3 (BCZT) powder and Bi 2 O 3 -B 2 O 3 -SiO 2 (BBS) glass-doped additives with different values of x ( x = 0, 0.05, 0.1, 0.15). Systematic investigations are performed to comprehend the structural, dielectric and energy storage characteristics using X-ray diffraction, field-emission scanning electron microscopy, impedance and ferroelectric analyser methods. With appropriate BBS doping ( x ), many fundamental traits including breakdown strength, dielectric loss and energy storage density have shown significant improvements. Low doping-level samples x < 0.1 have retained the pure perovskite phase while a second glass phase appeared in samples with x ≥ 0.1. As the doping level (0.1 ≥ x > 0) is increased, the average grain size decreased to become better homogeneous materials with improved breakdown energy strengths. Excessive addition of BBS ( x = 0.15) causes negative effects on microstructures and other traits. The glass-ceramic sample 0.95BCZT-0.05BBS exhibits excellent dielectric permittivity and temperature stability, with the highest energy storage density of 0.3907 J cm −3 at 130 kV cm −1 . These results provide good reference to develop lead-free ceramics of high energy storage density.