Unusual Magnetocaloric Effect Triggered by Spin Reorientation,Advanced Energy Materials

当前位置： X-MOL 学术 › Adv. Energy Mater. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Unusual Magnetocaloric Effect Triggered by Spin Reorientation
Advanced Energy Materials ( IF 24.4 ) Pub Date : 2024-09-05 , DOI: 10.1002/aenm.202402527
Yuzhu Song ₁ , Jimin Zhang ₁ , Hengchao Li ₁ , Hong Zhong ₁ , Feixiang Long ₁ , Zhan Wang ₂ , Yuanji Xu ₃ , Xinqi Zheng ₄ , Hu Zhang ₄ , Qingzhen Huang ₅ , Ying Zhang ₂ , Xianran Xing ₆ , Jun Chen _{1,

7}

Affiliation

Advancements and utilization of magnetic refrigeration technology hinge on the ongoing enhancement and optimization of magnetic refrigeration material properties. Nevertheless, the intricacy of the magnetocaloric effect (MCE) mechanism has emerged as a bottleneck, constraining the progress and refinement of magnetic refrigeration materials. In this study, a classic magnetic system is chosen to investigate the mechanism of MCE across four different scales–macroscopic magnetism, micrometer-scale magnetic domains, atomic magnetic moments, and electronic structure. It simultaneously exhibits two inverse MCEs and one direct MCE, with a working temperature span as wide as 125 K (most are <50 K) for the direct MCE. The measurements of the vibrating sample magnetometer, in situ Lorentz electron microscopy and variable-temperature neutron powder diffraction directly reveal that the complex magnetic entropy changes arise from the magnetic domain wall pinning, the instability of Ho magnetic moments, and the spin rotation. First-principles calculations elucidate the crucial role of strong hybridization between localized Ho and itinerant Co electrons in the spin reorientation of HoCo₄Al. This study contributes significantly to comprehending the induction mechanism of the MCE and holds vital reference value for exploring new magnetic refrigeration materials and enhancing MCE performance.

中文翻译：

自旋重新定向触发的不寻常磁热效应

磁制冷技术的进步和利用取决于磁制冷材料特性的不断增强和优化。然而，磁热效应（MCE）机制的复杂性已成为瓶颈，制约了磁制冷材料的进步和精细化。在这项研究中，选择了一个经典的磁性系统来研究 MCE 在四个不同尺度上的作用机制——宏观磁性、微米级磁畴、原子磁矩和电子结构。它同时表现出两个反向 MCE 和一个直接 MCE，直接 MCE 的工作温度跨度高达 125 K（大多数为 <50 K）。振动样品磁强计、原位洛伦兹电子显微镜和变温中子粉衍射的测量直接揭示了复杂的磁熵变化是由磁畴壁固定、Ho 磁矩的不稳定性和自旋旋转引起的。第一性原理计算阐明了局部 Ho 和流动 Co 电子之间的强杂化在 HoCo₄Al 的自旋重新取向中的关键作用。本研究对理解磁制冷的诱导机制具有重要意义，对探索新型磁制冷材料和提高磁制冷性能具有重要的参考价值。

更新日期：2024-09-05

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南