Effects of B-Site Donor Modification on the Crystal Structure and the Electrical Properties of Lead-Free 0.65BiFeO3-0.35BaTiO3 Ceramics

• Published in: Journal of the Korean Physical Society 2019, 75(10), , pp.811-816
• Main Authors: Khan, Salman Ali, Akram, Fazli, Kim, JunChan, Song, Tae Kwon, Kim, Myong-Ho, Lee, Soonil, Malik, Rizwan Ahmed, Hussain, Ali, Kim, Won-Jeong, Sung, Yeon Soo
• Format: Article
• Language: English
• Subjects: Air quenching; Crystal structure; Diffraction patterns; Electric fields; Electrical properties; Ferroelectric materials; Ferroelectricity; Grain size; Lead free; Mathematical and Computational Physics; Morphology; Particle and Nuclear Physics; Perovskite structure; Perovskites; Photomicrographs; Physics; Physics and Astronomy; Piezoelectric ceramics; Piezoelectricity; Theoretical; 물리학
• ISSN: 0374-4884; 1976-8524
• DOI: 10.3938/jkps.75.811

In the present work, lead-free piezoelectric ceramics 0.65Bi 1.05 Fe 1− x Ti x O 3 -0.35BaTi 1− y Nb y O 3 , where x = y = 0, 0.01, 0.015, 0.02, and 0.025, abbreviated as BFT-BTNb, were successfully synthesized by a solid-state reaction method and an air quenching method. The effects of B -Site donor modifications (Nb 5+ and Ti 4+ ) on the crystal structure, the morphology and the electrical properties of the 0.65BF-0.35BT ceramics were studied. X-ray diffraction patterns showed the formation of a pure perovskite structure, without any secondary phases. Scanning electron microscope (SEM) micrographs revealed that the average grain size of the BF-BT ceramics decreased with the addition of B -Site donors. Improvements in the ferroelectric properties ( P - E loops) and the electric field-induced strain properties ( S - E loops) were obtained at the optimum composition of the BFT-BTN ceramics. In addition, the dynamic piezoelectric coefficient ( d 33 * ) was enhanced from 265 pm/V for (BFT-BTNb-0) to 360 pm/V for (BFT-BTNb-1) with high working temperature, T m = 320 °C.