Multifunctional Pyroelectric and Electrocaloric response through Eu3+ doping in 0.55Pb(Ni1/3Nb2/3)O3-0.135PbZrO3-0.315PbTiO3 ceramics at Morphotropic Phase Boundary
Discuss this preprint
Start a discussion What are Sciety discussions?Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
This study presents a strategy to enhance the pyroelectric and electrocaloric responses at room temperature by tailoring the Landau free-energy landscape of a ternary morphotropic phase boundary (MPB) composition 0.55Pb(Ni 1/3 Nb 2/3 )O 3 -0.135PbZrO 3 -0.315PbTiO 3 + xEu 2 O 3 (x = 0, 0.01 & 0.02). Eu 3+ substitution at the A-site reduces the effective ionic spacing, inducing octahedral tilting and stabilizing a lower-symmetry crystal structure, predominantly rhombohedral, in the vicinity of room temperature. The associated local lattice distortion and charge imbalance promote relaxor behaviour in the PNN-PZ-PT system. A pronounced enhancement in pyroelectric performance is observed for the x = 0.02 composition, with the pyroelectric coefficient reaching ~ 33.34 ×10 − 4 C/m 2 K and the corresponding pyroelectric figures of merits (FOMs) attain values of \(\:{F}_{i}\) ~ 1993 pm/V, \(\:{F}_{v}\) ~ 0.01592 m 2 /C, \(\:{F}_{d}\) ~23.57 µ(Pa) −0.5 , \(\:{F}_{e}\) ~107 Jm 3 /K and \(\:{F}_{e}^{*}\) ~26.48 pm 3 /N. Notably, electrocaloric measurements reveal the emergence of an orthorhombic phase near room temperature, resulting in an improved electrocaloric temperature change. Concurrently, Eu 3+ doping suppresses the inverse piezoelectric coefficient (\(\:{d}_{33}^{*}\)) from 1036 pm/V for x = 0 to 460 pm/V for x = 0.02 sample indicating reduced electromechanical coupling, while the energy storage density exhibits an improvement near the ferroelectric-paraelectric phase transition. These findings demonstrate that Eu 3+ modified PNN-PZ-PT ceramics offer a tunable multifunctional platform with potential applications in solid-state cooling, infrared detection, and thermal energy harvesting.
