Large Room-Temperature Electrocaloric Response Realized in Potassium-Sodium Niobate by a Relaxor Enhancement Effect and Multilayer Ceramic Construct

Ye Zhao; Jinhua Du; Junlin Yang; Lipeng Zhu; Yanyu Wang; Yong Li; Xihong Hao

doi:10.1021/acsami.1c23622

Large Room-Temperature Electrocaloric Response Realized in Potassium-Sodium Niobate by a Relaxor Enhancement Effect and Multilayer Ceramic Construct

ACS Appl Mater Interfaces. 2022 Mar 9;14(9):11626-11635. doi: 10.1021/acsami.1c23622. Epub 2022 Feb 25.

Authors

Ye Zhao¹, Jinhua Du^{1

2}, Junlin Yang¹, Lipeng Zhu¹, Yanyu Wang¹, Yong Li¹, Xihong Hao¹

Affiliations

¹ Inner Mongolia Key Laboratory of Ferroelectric-Related New Energy Materials and Devices, School of Materials and Metallurgy, Inner Mongolia University of Science and Technology, Baotou 014010, China.
² School of Chemistry and Chemical Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, China.

PMID: 35212543
DOI: 10.1021/acsami.1c23622

Abstract

The development of high-performance electrocaloric (EC) materials is crucial for solid-state refrigeration applied in micro-electromechanical systems. Herein, a large room-temperature EC response is realized in (1 - x)(K_0.49Na_0.49Li_0.02)(Nb_0.8Ta_0.2)O₃-xCaZrO₃ (KNLNT-xCZ) benefiting from a relaxor enhancement effect and multilayer ceramic construct. The relaxor enhancement effect is because the long-range order is broken by adding CaZrO₃, which is in favor of enhancing the temperature change (ΔT) and broadening the temperature span (T_span) at room temperature. A ΔT of 0.48 K in the KNLNT-12CZ ceramic is ∼5 times higher than that in the KNLNT-8CZ ceramic at 30 °C. KNLNT-12CZ also exhibits good temperature stability, and the T_span is up to 65 K. In addition, the multilayer ceramic construct improves the breakdown electric field (E_b) through diminishing defects, leading to a booming ΔT of 3.2 K at 30 °C under 250 kV cm^-1 via a direct measurement. The work proposes an avenue for developing high-performance EC materials with a large EC response and broad T_span in solid-state refrigeration.

Keywords: broad temperature span; multilayer ceramic construct; potassium-sodium niobate; relaxor enhancement effect; room-temperature electrocaloric response.