Coexistence of positive and negative electrocaloric effects in lead free perovskite structured ferroelectrics

Sarir Uddin, Guang Ping Zheng, Yaseen Iqbal

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

The coexistence of positive and negative electrocaloric effects (ECE) was observed in the sol-gel derived Pb-free perovskite structured (Bi1/2Na1/2)1-xBaxTiO3 (x = 0, 0.04, 0.05, 0.06, 0.07) (BNBT) ceramics. The maximum electrocaloric temperature change of 2.35 °C has been observed at 100 kV/cm for x = 0.06 at about 70 °C before the ferroelectric to antiferroelectric (FE-to-AFE) phase transition temperature. The coexistence of positive and negative ECE at different temperatures may be attributed to two different temperature dependent phase transitions in the ferroelectrics or antiferroelectrics. The sign reversal of ECE in the same material can be utilized to increase the efficiency of the refrigeration cycle and to develop efficient environmentally friendly cooling systems.

Original languageEnglish
Article number105929
JournalSolid State Sciences
Volume95
DOIs
Publication statusPublished - 1 Sep 2019

Keywords

  • Electrocaloric effect
  • Ferroelectric ceramics
  • Lead-free
  • Solid state refrigerants

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics

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