Observation of diffuse relaxor activity and normal thermal stability in Ho – modified NBT – BT lead free ceramics

Abstract

Ho-modified NBT-BT ferroelectric ceramics were synthesized by a conventional solid state reaction. The changes in crystal structure and identification of functional groups in the prepared ceramics were studied by XRD and Raman studies. T-dependent dielectric study reveals a diffuse dielectric phase transitions were observed in the intervals of 200–$300°\mathrm{C}.$ A thermal stable dielectric constant was noted in long temperature intervals, with increases Ho-concentration. The polarization study indicates the deviation of loop shape from nearly square loop into slanted slim loop with Ho dopant. These observations indicate, NBHT-BT ceramics opens for energy harvesting and thermally stable dielectric materials applications.

Keywords:

• Lead free
• Sodium bismuth titanate (Na_0.5Bi_0.5TiO₃)-based
• relaxor

Acknowledgements

Authors would like to thank Dr. A.M. Awasthi and Dr. Suresh Bharadwaj, UGC-DAE, consortium at Indore center, India for providing Temperature dependent Dielectric measurements. And also, Special thanks to Dr. Vasant Sathe, for providing Raman scattering measurements. Author PT would like to thank for UGC-DAE Consortium, Mumbai center, India for financial support for Under CRS-M-216 project scheme.