Effect of the processing temperature on the electrical properties of lead-free 0.965Bi0.5Na0.5TiO3–0.035BaTiO3 piezoelectric ceramics synthesized by sol–gel method

• Published in: Journal of sol-gel science and technology Vol. 90; no. 3; pp. 643 - 652
• Main Authors: Munir, Muhammad, Habib, Muhammad, Khan, Salman Ali, Hussain, Ali, Qazi, Ibrahim, Bin Choi, Yeon, Son, Jeong-Hun, Malik, Rizwan Ahmad, Bae, Dong-Sik
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2019; Springer Nature B.V
• Subjects: Ceramics; Chemistry and Materials Science; Composites; Diffraction patterns; Electric fields; Electrical properties; electronic; Ferroelectric materials; Ferroelectricity; Glass; Grain size; Hysteresis loops; Inorganic Chemistry; Lead free; magnetic and ferroelectric applications; Materials Science; Morphology; Nanotechnology; Natural Materials; Optical and Electronic Materials; Original Paper: Sol–gel and hybrid materials for dielectric; Perovskite structure; Perovskites; Piezoelectric ceramics; Piezoelectricity; Scanning electron microscopy; Sintering (powder metallurgy); Sol-gel processes; Synthesis; X-ray diffraction; Polarization; Calcination; Lead-free piezoelectric; Sol–gel; Nano-particles; Sintering
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-018-04913-0

In this work, lead-free 0.965Bi 0.5 Na 0.5 TiO 3 –0.035BaTiO 3 (BNT–BT) piezoelectric ceramics were synthesized by a sol–gel process. X-ray diffraction pattern of the BNT–BT samples revealed that powder calcined at 600 °C, exhibit a pure perovskite structure. Scanning electron microscopy (SEM) was used to find the surface morphology and grain size of the investigated ceramics. At an optimized sintering temperature of 1150 °C, well-saturated ferroelectric ( P – E ) hysteresis loops with high remnant polarization ( P r  = 34.8 µC/cm 2 ) and low corrosive field ( E c  = 23 kV/cm) were obtained. Electric field-induced strain of 0.137% with a dynamic piezoelectric coefficient ( d 33 *  = 196 pm/V) was observed under 75 kV/cm drawing field. In addition, high static piezoelectric constant ( d 33  = 138 pC/N) was recorded for the sample sintered at 1150 °C. This value of d 33 is comparable to that of BNT-based bulk piezoelectric ceramics. BNT–BT nano-particles were prepared by using the acetic-acid sol–gel process, calcined at 600 °C and sintered at 1150 °C to get the optimum processing temperature. Well saturated and square type P–E hysteresis loops were obtanied with high remnant polarization ( P r  = 34.8 µC/cm 2 ) equivalent to the BNT-bulk ceramcis which were prepared through the conventional solid state reaction method [ 1 , 2 ]. The high static piezoelectric constant 138 pC/N was obtained which is comparable to the BNT-based bulk ceramics [ 3 ] Highlights In this work, lead-free 0.965Bi 0.5 Na 0.5 TiO 3 –0.035BaTiO 3 (BNT-BT) piezoelectric ceramics were synthesized by a sol-gel process. X-ray diffraction pattern of the BNT-BT samples revealed that powder calcined at 600 °C, exhibit a pure perovskite structure. Scanning electron microscopy (SEM) was used to find the surface morphology and grain size of the investigated ceramics. At an optimized sintering temperature of 1150 °C, well saturated ferroelectric (P–E) hysteresis loops with high remnant polarization ( P r = 34.8 μC/cm 2 ) and low corrosive field ( E c = 23 kV/cm) were obtained. Electric field-induced strain of 0.137% with a dynamic piezoelectric coefficient (d33 *  = 196 pm/V) was observed under 75 kV/cm drawing field. In addition, high static piezoelectric constant ( d 33 = 138 pC/N) was recorded for the sample sintered at 1150 °C. This value of d 33 is comparable to that of BNT-based bulk piezoelectric ceramics.