INFLUENCE OF SINTERING TEMPERATURE ON STRUCTURE AND OPTICAL PROPERTIES OF BiFeO3-BaTiO3 MATERIALS

Tóm tắt

The multiferroic 0.7BiFeO₃-0.3BaTiO₃ materials was synthesized via the sol-gel method at sintering temperatures of 800 ºC, 850 ºC, 900 ºC, and 950 ºC to examine the effect of sintering temperature on its structure and optical properties. X-ray diffraction analysis confirmed the coexistence of the rhombohedral R3c phase of BiFeO₃ and the tetragonal P4mm phase of BaTiO₃. With increasing sintering temperature, a gradual transition from the rhombohedral phase to the tetragonal phase was observed. Furthermore, the grain size of the material increased as the sintering temperature rose. The optical bandgap (E_g) of BiFeO₃- BaTiO₃ decreased slightly from 2.02 eV at 800 ºC to 1.96 eV at 950 ºC. These structural and optical changes are attributed to the phase transition from rhombohedral to tetragonal symmetry induced by higher sintering temperatures. This study highlights the influence of sintering temperature on the structure and optical properties of BiFeO₃- BaTiO₃, demonstrating its potential for multifunctional devices when sintered at optimal temperatures.