Si Mengwei, Saha Atanu K, Liao Pai-Ying, Gao Shengjie, Neumayer Sabine M, Jian Jie, Qin Jingkai, Balke Wisinger Nina, Wang Haiyan, Maksymovych Petro, Wu Wenzhuo, Gupta Sumeet K, Ye Peide D
School of Electrical and Computer Engineering , Purdue University , West Lafayette , Indiana 47907 , United States.
Birck Nanotechnology Center , Purdue University , West Lafayette , Indiana 47907 , United States.
ACS Nano. 2019 Aug 27;13(8):8760-8765. doi: 10.1021/acsnano.9b01491. Epub 2019 Aug 6.
A material with reversible temperature change capability under an external electric field, known as the electrocaloric effect (ECE), has long been considered as a promising solid-state cooling solution. However, electrocaloric (EC) performance of EC materials generally is not sufficiently high for real cooling applications. As a result, exploring EC materials with high performance is of great interest and importance. Here, we report on the ECE of ferroelectric materials with van der Waals layered structure (CuInPS or CIPS in this work in particular). Over 60% polarization charge change is observed within a temperature change of only 10 K at Curie temperature. Large adiabatic temperature change (|Δ|) of 3.3 K and isothermal entropy change (|Δ|) of 5.8 J kg K at |Δ| = 142.0 kV cm and at 315 K (above and near room temperature) are achieved, with a large EC strength (|Δ|/|Δ|) of 29.5 mK cm kV. The ECE of CIPS is also investigated theoretically by numerical simulation, and a further EC performance projection is provided.
一种在外部电场作用下具有可逆温度变化能力的材料，即电热效应（ECE），长期以来一直被视为一种很有前景的固态冷却解决方案。然而，电热（EC）材料的EC性能通常对于实际冷却应用来说不够高。因此，探索高性能的EC材料具有极大的兴趣和重要性。在此，我们报道了具有范德华层状结构的铁电材料（特别是本工作中的CuInPS或CIPS）的ECE。在居里温度下，仅10 K的温度变化范围内就观察到超过60%的极化电荷变化。在|Δ| = 142.0 kV/cm和315 K（高于且接近室温）时，实现了3.3 K的大绝热温度变化（|Δ|）和5.8 J kg K的等温熵变（|Δ|），以及29.5 mK cm kV的大EC强度（|Δ|/|Δ|）。还通过数值模拟从理论上研究了CIPS的ECE，并给出了进一步的EC性能预测。
