Effect of sintering temperature on morphology, dielectric and ferroelectric properties of five layer Aurivillius oxides: A_2Bi_4Ti_5O_(18) (A=Ba, Pb and Sr) synthesized by co-precipitation route

摘要

Polycrystalline ceramics with chemical formula Ba_2Bi_4Ti_5O_(18), Pb_2 Bi_4Ti_5O_(18) and Sr_2Bi_4Ti_5O_(18) have been synthesized using co-precipitation route. In the present study optimization of calcination and sintering temperature is carried out and the relationship between sintering temperature and morphology, dielectric, and ferroelectric properties of the as-prepared samples is extensively investigated. Pellets of these samples were sintered at a range of temperatures 850, 950 and 1050 °C for 2 h. The phase formation of compounds calcined at different temperatures was studied using X-ray diffraction and scanning electron microscopy was used to examine the surface morphology. Crystallite and grain size was seen to increases with an increase in the calcination and sintering temperature respectively. The dielectric and ferroelectric properties of the ceramics were found to improve at a higher sintering temperature.