X-ray and dielectric studies of ferroelectric or relaxor phases in the Ca1−xNaxSn1−xNbxO3 system

New relaxor ceramic with composition BaTi1−x(Zn1/3Nb2/3)xO3

“…Barium titanate ceramic is interesting because it presents a * Corresponding author. This material belongs to the perovskite family ABO 3 ; many investigations reported that homovalent or heterovalent substitutions of barium or titanium ions lead to remarkable changes in various characteristics [8][9][10][11][12][13][14][15][16]. Ravez and Simon proved that the replacement of Ti 4+ by Zr 4+ changes significantly the dielectric and structural properties of BaTiO 3 :BaTi 1−x Zr x O 3 (BTZ) is relaxor ferroelectric for substitution rate higher than about 25% [17].…”

Strain Mechanisms in Lead-Free Ferroelectrics for Actuators

“…[114][115][116]  An average long-range pseudocubic structure is not always observed in lead-free relaxors. 117  Local antiferroelectric PNRs were proposed. 118  A distribution in the degree of ergodicity may develop locally, which could be ascribed to different coexisting symmetries of PNRs.…”

X-ray diffraction, dielectric measurements and Raman spectroscopy

“…Pure NaNbO 3 is antiferroelectric at room temperature, with orthorhombic distorted perovskite structure; it easily becomes ferroelectric by low rate substitutions [7,8]. The crystalline structure of the calcium stannate CaSnO 3 is also a distorted perovskite with a center of symmetry [7,8].…”

“…The crystalline structure of the calcium stannate CaSnO 3 is also a distorted perovskite with a center of symmetry [7,8]. Recent studies reveal the potentially interesting properties of these materials as thermally stable capacitors with low permittivity and weak tangent loss [7,8]. The relaxor effect was attributed to the presence of a cationic disorder in the A (C.N.…”

“…In order to investigate the morphology and the grain size a MEB study was also carried out using JEOL JED2300 [7,8].…”