Solid state materials for magnetic refrigiration: polar intermetallics of main group p-elements and 3d- and 4f-metals as promising magnetocaloric agents

用于磁制冷的固态材料：主族 p 元素以及 3d 和 4f 金属的极性金属间化合物作为有前景的磁热剂

• 批准号: 327816-2006
• 负责人: Mozharivskyj, Yurij
• 金额: $ 2.33万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=365900
• 关键词: Solid; state; materials; magnetic; refrigiration

This grant application is requesting funds for establishing a research program in chemistry of magnetocaloric materials. The research will focus on design, synthesis and characterization of new magnetocaloric materials in which ferromagnetic and structural transitions are coupled. Such materials produce a large temperature response with a change in magnetic field and can be used for refrigeration and air-conditioning. Currently understudied and underutilized, magnetocaloric cooling agents offer better efficiency, simpler mechanical design and are more environmentally friendly than vapor cooling agents used in regular refrigerator units. Progress in this area depends strongly on the discovery of new phases with good stability, high cooling capacity and useful operational temperatures. A key to achieving good magnetocaloric properties is to couple a ferromagnetic ordering to a first-order structural transition; the enthalpy associated with the structural transition enhances the temperature response and increases the cooling efficiency of the material. In this respect, structurally flexible polar intermetallic phases of 4f-, 3d- and p-elements present good opportunities for discovery of new magnetocaloric phases. The research in my group will pursue four distinct directions: - modification of the magnetic LnCo5 phases along the Ln(Co1-xBx)5 compositional lines; - exploration of the magnetic spinel phases; - investigation of the rare-earth rich parts of the ternary Ln-T-Sb and Ln-T-Bi systems (T = Fe, Co and Ni); - study of the transition metal rich parts of the Ln-Co-P and Ln-Ni-P systems.

本基金申请是为了建立一个磁热材料化学研究项目而申请的。该研究将集中在新的磁热材料的设计，合成和表征，其中铁磁和结构转变耦合。这种材料随着磁场的变化产生大的温度响应，可用于制冷和空调。目前研究和利用不足，磁热冷却剂提供更好的效率，更简单的机械设计，比常规冰箱中使用的蒸汽冷却剂更环保。这一领域的进展主要取决于发现具有良好稳定性、高冷却能力和有用操作温度的新相。实现良好磁热性能的关键是将铁磁有序化与一阶结构转变相结合;与结构转变相关的焓增强了温度响应并提高了材料的冷却效率。在这方面，4f-、3d-和p-元素的结构柔性极性金属间相为发现新的磁热相提供了良好的机会。本课题组的研究将从四个不同的方向进行：-沿Ln（Co 1-xBx）5组成线沿着改变磁性LnCo 5相; -探索磁性尖晶石相; -研究三元Ln-T-Sb和Ln-T-Bi系统（T = Fe、Co和Ni）的富稀土部分; -研究Ln-Co-P和Ln-Ni-P系统的富过渡金属部分。