X-ray diffraction, dielectric measurements and Raman spectroscopy

Structure properties and dielectric relaxation of Ca0.1Na0.9Ti0.1Nb0.9O3 ceramic

“… 57 Therefore, the origin of the observed relaxor behavior with DPT in CNTN sample is due to the inhomogeneous distribution assigned to the compositional fluctuation, resulting in the microscopic heterogeneity with various Curie points and giving rise to the detected behavior Relaxor. 58 Furthermore, the creation of the Coulomb interactions at long distance inhibits the formation of ferroelectric microdomains in favor of the formation of the PNRs. Under these conditions, the order becomes short.…”

Electrical, optical and photoelectrochemical properties of BaSnO3−δ

“…1) is indexed in a cubic unit cell as evidenced from the tolerance factor t (1.01: considering Shannon ionic radii). The lattice constant {a = 0.4117(2) nm; } is slightly larger than that of BaSnO 3 {0.4115 (3) nm}; this implies an increase of the unit cell volume ( V = 0.0698 nm 3 ) induced by the oxygen under-stoichiometry. This is attributed to a small amount of Sn 2+ (r Sn 2+ = 0.110 nm) in six-fold coordination [18], generated by a charge compensation mechanism, smaller than Sn 4+ (r Sn 4+ = 0.110 nm).…”

“…They have also been studied for possible applications of the light-toelectrical and/or chemical energy conversion [2], stable capacitors [3] and oxygen-permeable ceramic membranes [4]. BaSnO 3 is classified as a wide band gap semiconductor where the conduction band (CB), originating from anti bonding mixture of Sn: 5s-O 2− : 2p orbital, is separated from the broad valence band (VB) of anionic O 2− : 2p parentage by a gap exceeding 3 eV [5].…”

Structure, dielectric and piezoelectric properties of NaNbO3–Ba0.6(Bi0.5K0.5)0.4TiO3 lead-free ceramics

“…NaNbO 3 and its related perovskite materials have attracted much attention because of their interesting electrical and mechanical properties [4][5][6][7][8][9][10][11][12][13]. Many NaNbO 3 -based lead-free systems, such as NaNbO 3 -CaTiO 3 [7], NaNbO 3 -SrTiO 3 [8], NaNbO 3 -BaTiO 3 [9], NaNbO 3 -BaSnO 3 [10], NaNbO 3 -CaSnO 3 [11], NaNbO 3 -BaSnO 3 -BaTiO 3 [12], and NaNbO 3 -BiCrO 3 [13], have been developed by the incorporation of ABO 3 -type compounds into NaNbO 3 , but these studies mostly focus on their dielectric properties because of their remarkable relaxor characteristics. It is also noted that the substitution of a small amount of K + [4] and Li + for Na + [14] will transform NaNbO 3 ceramics from an antiferroelectric to a ferroelectric.…”