{"title":"Structural and dielectric characteristics of 0.50 Bi/sub 2/O/sub 3/-0.25 V/sub 2/O/sub 5/-0.25 SrB/sub 4/O/sub 7/ glass-ceramic","authors":"M. Shankar, K. Varma","doi":"10.1109/ISAF.1996.598149","DOIUrl":null,"url":null,"abstract":"Novel 0.50 Bi/sub 2/O/sub 3/-0.25 V/sub 2/O/sub 5/-0.25 SrB/sub 4/O/sub 7/ glasses have been prepared via a conventional splat-quenching technique. Differential thermal analysis (DTA) carried out on the as-quenched samples confirms their glassy nature and shows a prominent exothermic peak at 400/spl deg/C. The X-ray powder diffraction (XRD) pattern of the heat treated sample could be indexed to an orthorhombic ferroelectric Bi/sub 2/VO/sub 5.5/ phase with the lattice parameters a=5.543, b=5.615 and c=15.321 A. The presence of nano-crystallites of bismuth vanadate, Bi/sub 2/VO/sub 5.5/ (BiV) dispersed in the glassy matrix of strontium tetraborate, SrB/sub 4/O/sub 7/ (SBO) is confirmed in the heat treated (at 400/spl deg/C for 12 h) samples, by high resolution transmission electron microscopy (HRTEM). The dielectric constant (/spl epsiv//sub /spl tau//), measured as a function of temperature, exhibits an anomaly around the transition temperature of the parent crystalline BiV. The /spl epsiv//sub /spl tau// of the glass-ceramic at 300K is comparable with that predicted by Maxwell's model and logarithmic mixture rule.","PeriodicalId":14772,"journal":{"name":"ISAF '96. Proceedings of the Tenth IEEE International Symposium on Applications of Ferroelectrics","volume":"1 1","pages":"817-820 vol.2"},"PeriodicalIF":0.0000,"publicationDate":"1996-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ISAF '96. Proceedings of the Tenth IEEE International Symposium on Applications of Ferroelectrics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/ISAF.1996.598149","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Novel 0.50 Bi/sub 2/O/sub 3/-0.25 V/sub 2/O/sub 5/-0.25 SrB/sub 4/O/sub 7/ glasses have been prepared via a conventional splat-quenching technique. Differential thermal analysis (DTA) carried out on the as-quenched samples confirms their glassy nature and shows a prominent exothermic peak at 400/spl deg/C. The X-ray powder diffraction (XRD) pattern of the heat treated sample could be indexed to an orthorhombic ferroelectric Bi/sub 2/VO/sub 5.5/ phase with the lattice parameters a=5.543, b=5.615 and c=15.321 A. The presence of nano-crystallites of bismuth vanadate, Bi/sub 2/VO/sub 5.5/ (BiV) dispersed in the glassy matrix of strontium tetraborate, SrB/sub 4/O/sub 7/ (SBO) is confirmed in the heat treated (at 400/spl deg/C for 12 h) samples, by high resolution transmission electron microscopy (HRTEM). The dielectric constant (/spl epsiv//sub /spl tau//), measured as a function of temperature, exhibits an anomaly around the transition temperature of the parent crystalline BiV. The /spl epsiv//sub /spl tau// of the glass-ceramic at 300K is comparable with that predicted by Maxwell's model and logarithmic mixture rule.