Open AccessEnhancing dielectric permittivity for energy-storage devices through tricritical phenomenon
Author(s) -
Jinghui Gao,
Yan Wang,
Yongbin Liu,
Xinghao Hu,
Xiaoqin Ke,
Yuting He,
Xiaobing Ren
Publication year - 2017
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep40916
Subject(s) - dielectric , electric field , permittivity , condensed matter physics , materials science , polarization density , ferroelectricity , vacuum permittivity , polarizability , electric susceptibility , polarization (electrochemistry) , relative permittivity , optoelectronics , physics , magnetic field , chemistry , magnetization , quantum mechanics , molecule
Although dielectric energy-storing devices are frequently used in high voltage level, the fast growing on the portable and wearable electronics have been increasing the demand on the energy-storing devices at finite electric field strength. This paper proposes an approach on enhancing energy density under low electric field through compositionally inducing tricriticality in Ba(Ti,Sn)O 3 ferroelectric material system with enlarged dielectric response. The optimal dielectric permittivity at tricritical point can reach to ε r = 5.4 × 10 4 , and the associated energy density goes to around 30 mJ/cm 3 at the electric field of 10 kV/cm, which exceeds most of the selected ferroelectric materials at the same field strength. The microstructure nature for such a tricritical behavior shows polarization inhomogeneity in nanometeric scale, which indicates a large polarizability under external electric field. Further phenomenological Landau modeling suggests that large dielectric permittivity and energy density can be ascribed to the vanishing of energy barrier for polarization altering caused by tricriticality. Our results may shed light on developing energy-storing dielectrics with large permittivity and energy density at low electric field.