Structure and temperature dependent electrical properties of lead-free Bi0.5Na0.5TiO3- SrZrO3 ceramics

Lead-free SrZrO3-modified Bi0.5Na0.5TiO3 (BNT-SZ) ceramics were fabricated by a conventional solid state reaction method. X-ray diffraction analysis reveals a pure perovskite phase without any traces of secondary phases. Scanning electron microscopy images depicts dense grain morphology. The temperature dependences of the dielectric behavior was measured in the temperature range of 50-500 °C at 100 kHz. With the increase in SZ content, the dielectric constant (ϵr) constantly decreased and the maximum dielectric constant temperature (Tm) shifted towards lower temperatures. In addition to this, ferroelectric hysteresis loops indicated a disruption of ferroelectric order and increase in the relaxor character of BNT ceramics with increase in SZ concentration. A maximum values of remnant polarization (32 μC/cm2) and piezoelectric constant (100 pC/N) were observed at SZ5 and SZ4, respectively.