在NdSmNiMnO6双矿的第二阶段铁磁 - 磁性相位过渡中,磁热效应和关键行为
John M Attah-Baah1, Romualdo S Silva2, Cledson Santos3
1Departamento de Física, Universidade Federal de Sergipe, 49100-000 São Cristóvão, SE, Brazil.
ACS omega
|May 19, 2025
概括
研究人员合成了一种新型的双矿,NdSmNiMnO6,证明了有前途的磁热效应 (MCE) 对于环保冷却. 这种材料在相位过渡附近表现出显著的磁变化,表明其作为磁性制冷剂的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 开发高效和环保的冷却技术至关重要.
- 磁冷却为传统冷却方法提供了一个可持续的替代方案.
- 在磁性固体中优化磁热效应 (MCE) 是一个关键的挑战.
研究的目的:
- 为了合成和表征双矿 NdSmNiMnO.
- 调查其磁热效应 (MCE) 和关键行为.
- 评估其作为磁性制冷剂材料的潜力.
主要方法:
- 经过修改的sol-gel合成过程.
- 用于晶体结构分析的X射线衍射.
- 磁热效应测量和关键行为分析 (修改的阿罗特图,Kouvel-Fisher方法,关键等温分析).
主要成果:
- NdSmNiMnO6 在单临床P21/n空间组中结晶.
- 在180K相位过渡附近观察到 -ΔSMmax = 2.38 J kg-1 K-1的最大磁变化.
- 在0-7 T电场下,相对冷却功率达到~182 J kg-1 .
- 确定了临界指数 (β = 0.469, γ = 0.978, δ = 3.09),与缩放理论一致.
结论:
- NdSmNiMnO6是磁性制冷的一个有前途的材料,因为它的显著的MCE.
- 关键行为受到长距离和短距离磁相互作用之间的竞争的影响.
- 对此类材料的进一步研究可能会导致先进的冷却解决方案.
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