Dielectric properties of Sr1+XBi2−(2/3)X(VXTa1−X)2O9 [, 0.1 and 0.2] ceramics

Investigation on microstructure, dielectric and impedance properties of Sr1−Bi2+(2/3)(V Ta1−)2O9 [x= 0, 0.1 and 0.2] ceramics

“…perature. Similar to Sr 1+x Bi 2−(2/3)x (V x Ta 1−x ) 2 O 9 [28] negative shift of Curie temperature as a function of frequency was observed for Sr 1−x Bi 2+(2/3)x (V x Ta 1−x ) 2 O 9 . Strong frequency dispersion of dielectric constant and Curie temperature shifting towards higher temperature with an increasing frequency are characteristic of relaxor ferroelectrics.…”

“…Systematic studies on the dielectric properties of Sr 1+x Bi 2−(2/3)x (V x Ta 1−x ) 2 O 9 [where x = 0, 0.1 and 0.2] were reported earlier [28]. In the present work, structural, microstructural, dielectric and impedance properties of…”

“…This structural distortion could be the reason for the observed higher Curie temperature in this composition. Among the investigated compositions Sr 1+x Bi 2−(2/3)x (V x Ta 1−x ) 2 O 9 [28] and Sr 1−x Bi 2+(2/3)x (V x Ta 1−x ) 2 O 9 with x = 0.1 and 0.2 the maximum peak dielectric constant is observed for Sr 1−x Bi 2+(2/3)x (V x Ta 1−x ) 2 O 9 ceramics with x = 0.2. Another interesting observation in the temperature dependent dielectric constant measurements is that the phase transitions are much sharper in Sr 1−x Bi 2+(2/3)x (V x Ta 1−x ) 2 O 9 compared to Sr 1+x Bi 2−(2/3)x (V x Ta 1−x ) 2 O 9 [28].…”

“…Recently efforts have been made to enhance the properties of layered perovskite ferroelectrics by the addition or substitution in both A-(Sr 2+ ) and B-(Ta 5+ ) site in these perovskite ferroelectric materials [26][27][28][29][30][31]. Shyam Prasad and Varma reported the structural and dielectric properties of Sr 1−x Ba x Bi 2 (Nb 0.5 Ta 0.5 ) 2 O 9 and Sr 0.5 Ba 0.5 Bi 2 (Nb 1−y Ta y ) 2 O 9 solid solutions [27].…”

Dielectric properties of Sr0.8Bi2.2(V0.2Nb0.8)2O9 ceramic

“…Higher dielectric constant at the transition temperature observed for SBVN compared to SBN was attributed to the partial substitution of pentavalent niobium ions (Nb 5+ : 69 pm) by smaller pentavalent vanadium ions (V 5+ : 59 pm) in the B site of layered perovskite structure, which leads to an increased "rattling space" for the cations inside the oxygen octahedron. In our recent work higher Curie temperature and enhanced dielectric constant was observed at the transition temperature for Sr 1+x Bi 2−(2/3)x (V x Ta 1−x ) 2 O 9 [x = 0.1 and 0.2] [14].…”