Effect of rare-earth ions on the properties of modified (SrBa)Nb2O6 ceramics

Abstract

Strontium barium niobate is a tetragonal tungsten bronze solid solution. It has been extensively investigated in single-crystal form by Glass [1] and Liu and Maciolek [2] for pyroelectric applications and by Jamieson et al. [3] from the structural point of view. Filled SBN compositions have been investigated in single-crystal form by Chen and Cross [4], and we have previously reported the ferroelectric properties of modified SBN [3] ceramics of filled compositions.In this letter the effect of doping rare-earth ions on SBN ceramics modified with Na + and K + are investigated. The general formula of the solid solutions is Ro.06Sro.48Bao.30Naoj2KoJ4Nb20 6 where R = Ce 3+,

Phase formation, microstructure and dielectric properties of Sr0.53Ba0.47Nb2−xTaxO6 ceramics

“…Dielectric constant εr and dielectric loss tan ı for Sr0.53Ba0.47Nb2−xTaxO6 ceramics around room temperature as a function of x. [12]. The T c decreases with Ta 5+ concentration may be due to the structure vacancies which made by Ta 5+ (0.068 nm) substituted for Nb 5+ (0.069 nm).…”

“…Many physical and chemical properties may vary significantly by desired impurities doping or substituting [10,11]. For instance, alkali elements' doping on SBN showed a great increase in transition temperature and a decrease in dielectric loss [12]. Nishiwaki et al found that rare earth elements (RE) and Li ions increased the transition temperature with decreasing the RE ionic ratio [15].…”

Structural and dielectric properties of (Li0.5Na0.5) doped strontium barium niobate

“…16͒ crystal structure having P4bm space group 17 and approximate lattice parameters a = b = 1.24 nm, c = 0.39 nm. 33,34 In the present work we had doped SBN ͑61/ 39͒ with alkali elements in order to study its effects on phase transition temperature, dielectric and grain boundary resistance properties. 6 Investigations using x-ray diffraction suggested a morphotropic phase boundary around x = 25, which is characterized by the coexistence of the tetragonal and orthorhombic phases.…”

Effect of V2O5 on sintering behaviour, microstructure and dielectric properties of textured Sr0.4Ba0.6Nb2O6 ceramics

“…However, in comparison with the sample prepared without seed particles, the samples prepared with seed particles have higher T c value, showing that the addition of seed particles influences the T c of SBN40 value. Previous investigation 18,19 shows that when alkali elements, such as sodium and potassium, are present in the structure, they will partially or fully occupy the interstitial sites with no vacancy left and this causes the value of T c to increase, which stabilises the ferroelectric structure. From Table 2, T c of the sample prepared without seed particles and V 2 O 5 approaches single crystal SBN40 (T c = 158 • C).…”