Relaxor behavior in (Ba1−3x/2Bix)(ZryTi1−y)O3 ceramics

New ferroelectric ceramics Bi-BZT of ABO3 perovskite type were synthesized in the (Ba1−3x/2Bix)(ZryTi1−y)O3 system by solid state reaction route. The effect of the substitution of barium by bismuth in the A cationic site on structural and dielectric properties was investigated. The dielectric constant was studied in the temperature range from 20 K to 320 K at frequencies ranging from 0.2 to 100 kHz. A clear relaxor behavior was observed for samples with x ≥ 0.075 and y = 0.1. In this case the value of the relaxation parameter γ ≈ 2 estimated from the linear fit of the modified Curie–Weiss law, indicates the relaxor nature of the Bi-BZT ceramics. The dielectric relaxation rate follows Vogel–Fulcher relation with an activation energy of 0.26 eV and 0.27 eV, an attempt frequency f0 = 3.4 × 1012 Hz and 5.7 × 1012 Hz and a static freezing temperature TVF = 98 K and 94 K respectively for x = 0.075 and x = 0.1.