Inverse barocaloric effects in ferroelectric BaTiO3 ceramics
Auteurs
E. Stern-Taulats, P. Lloveras, M. Barrio, E. Defay, M. Egilmez, A. Planes, J. L. Tamarit, L. Mañosa, N. D. Mathur, and X. Moya
Référence
APL Materials, vol. 4, no. 9, art. no. 091102, 2016
Description
We use calorimetry to identify pressure-driven isothermal entropy changes in ceramic samples of the prototypical ferroelectric BaTiO3. Near the structural phase transitions at -400 K (cubic-tetragonal) and -280 K (tetragonal-orthorhombic), the inverse barocaloric response differs in sign and magnitude from the corresponding conventional electrocaloric response. The differences in sign arise due to the decrease in unit-cell volume on heating through the transitions, whereas the differences in magnitude arise due to the large volumetric thermal expansion on either side of the transitions.
