Preparation and electrical properties of Bi0.5Na0.5TiO3–BaTiO3–KNbO3 lead-free piezoelectric ceramics

Low sintering temperature and high piezoelectric properties of Li-doped (Ba,Ca)(Ti,Zr)O3 lead-free ceramics

“…However, the environmental concerns urgently require lead-free ceramics to substitute for the PZT with high content of toxic lead [1,2]. BaTiO 3 (BT) is one of the good candidates for lead-free ceramics due to its promising piezoelectric properties and solid solution with other perovskites, such as BT-KNbO 3 [3], BT-Bi(Mg 1/2 Ti 1/2 )O 3 [4], BT-Bi 0.5 Na 0.5 TiO 3 -Bi 0.5 K 0.5 TiO 3 [5], BT-Bi(Zn 1/2 Ti 1/2 )O 3 -BiFeO 3 [6], BT-Bi 0.5 Na 0.5 TiO 3 -KNbO 3 [7], Bi 0.5 Na 0.5 TiO 3 -(Ba,Ca)(Ti,Zr)O 3 [8], (Ba,Ca)(Ti,Sn)O 3 -(Ba,Ca)(Ti,Zr)O 3 [9], BT-CaTiO 3 -BaHfO 3 [10]. Among them, the BaTi 0.8 Zr 0.2 O 3 -(Ba 0.7 Ca 0.3 )TiO 3 (BCTZ) composition lead-free ceramics, which were reported by Liu and Ren [11], have been attracted great attention because of their high piezoelectricity arising from the polymorphic phase transition (PPT) at room temperature.…”

Piezoelectric and ferroelectric properties of (Bi1−xNa0.8K0.2Lax)0.5TiO3 lead-free ceramics

“…5, the dielectric anomaly peaks at T m for all the ceramics are relatively broad, indicating that the phase transition at T m is a diffuse phase transition. Diffuse phase transition has always been observed in BNT-based ceramics [30,31], of which either the A-sites or B-sites are occupied by at least two cations. Na + , K + , Bi 3+ and La 3+ are randomly distributed in A-sites for (Bi 1−x Na 0.8 K 0.2 La x ) 0.5 TiO 3 ceramics, so the observed diffuse phase transition behavior near T m is reasonably attributed to the disordering of A-site cations.…”

“…Some researchers roughly propose that the anomalies in the P-E loop resulted from the electromechanical interaction between the polar and the non-polar regions, which coexist in the ceramics at above T d [24,36,37]. Some researchers consider that macro-micro domain transition occurs near T d in BNT-based ceramics [30,31]. Most of the researchers consider that the appearance of the constricted hysteresis loop near T d stems from phase transition from a ferroelectric phase to an anti-ferroelectric phase [33][34][35][38][39][40][41], which results in a large electric-field-induced strain.…”

Phase transitions and dielectric properties of (1 − x)KNbO3 − xK0.5Bi0.5TiO3 ceramics synthesized by a stirred hydrothermal process

“…Nb 2⁄ 3 )O3 [21], Na 0.5 Bi 0.5 TiO 3 -K 0.5 Bi 0.5 TiO 3[22],NaNbO 3 -CaTiO 3[23]. It is found that the dielectric properties of (1-x)KBT-xKN system increased with the increase of KBT contents.…”

“…For these reasons, potassium niobate KNbO 3 (KN) which is considered the based solid solution, has been largely studied [1][2][3][4]. It is a ferroelectric material with a high Curie temperature, Tc=435°C.…”