通过格子振动和离子扩散介导的塑料晶体中的巨大可逆的巴罗卡洛里效应
Ming Zeng1, Carlos Escorihuela-Sayalero1, Tamio Ikeshoji2
1Grup de Caracterizació de Materials, Departament de Física, EEBE and Barcelona Research Center in Multiscale Science and Engineering Universitat Politècnica de Catalunya, Av. Eduard Maristany 10-14, Barcelona, 08019, Catalonia, Spain.
概括
在LiCB11H12中发现巨大的热量效应 (BCE),以实现可持续的固态冷却. 这种材料在相位过渡附近表现出大,可逆的温度和变化,为传统冷却技术提供了有希望的替代方案.
科学领域:
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
- 固态物理 固态物理
背景情况:
- 固态冷却/加热为当前技术提供了一个可持续的替代方案.
- 由水位压力 (p) 驱动的巴罗卡洛里效应 (BCE) 对大温度和变化有希望.
- 挑战包括大压力转移和在同一材料中实现显著的 ΔT 和 ΔS.
研究的目的:
- 在LiCB11H12.12中展示巨大的和可逆的 BCE.
- 为了调查 BCE 接近物质的顺序-混乱阶段过渡在~380 K.
- 量化格子振动,分子重定向和离子扩散对 BCE 的贡献.
主要方法:
- 实验测量在水静压下对亚热热温度变化 (水静ΔT下) 和同热变化 (水静ΔS下) 的测量.
- 利用分子动力学模拟来分析 BCE 的潜在机制.
- 研究格子振动,分子重定位和离子扩散的作用.
主要成果:
- 巨大的和可逆的BCE在LiCB11H12中显示在380K附近.
- 实现了 ΔS_rev 下载 = 280 J K-1 kg-1 和 ΔT_rev 下载 = 32 K 的 Δp ≈ 0.23 GPa.
- ≈2 J K-1 kg-1 MPa-1 的高可逆热量强度观察到 Δp ≈0.1 GPa.
- 格子振动显著促进了ΔS,而离子扩散对于相位过渡至关重要.
结论:
- LiCB11H12表现出最先进的巨大热量效应,与当前的基准标准相竞争.
- 该材料为高效和可持续的固态冷却和加热应用提供了一个有前途的途径.
- 了解格子动力学和离子扩散的相互作用是优化 BCE 材料的关键.
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