Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7887532 | Ceramics International | 2018 | 30 Pages |
Abstract
The electrocaloric effect (ECE) of Mn doped Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT:Mn) single crystals with particular emphasis on the impact of crystallographic orientations and phase transitions were investigated systematically. Orientation-dependent phase transitions have been demonstrated by the dielectric and strain behaviors. Intriguingly, the negative ECE of -0.02â¯Â°C and -0.002â¯Â°C were obtained firstly in [001]-oriented PIN-PMN-PT:Mn crystals near the rhombohedralâtetragonal phase transformation and in [011]-oriented crystals near the rhombohedralâorthorhombic phase transformation, respectively. However, only the positive ECE was found in [111]-oriented crystals near the tetragonalârhombohedral phase transition. Additionally, the maximum ECE temperature changes calculated in [001]-, [011]- and [111]-oriented crystals were 0.33â¯Â°C, 0.46â¯Â°C and 0.38â¯Â°C, respectively. Our results suggest that the negative ECE is attributed to electric field-induced phase transitions, whose critical field decreases with the increase of temperature. The phase transition-mediated coexistence of positive and negative effects in the relaxor-ferroelectric single crystals is beneficial to enhance the efficiency of the solid-state cooling devices.
Related Topics
Physical Sciences and Engineering
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Authors
Yaming Zhou, Qiang Li, Fangping Zhuo, Qingfeng Yan, Yiling Zhang, Xiangcheng Chu,