• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>RSC Advances >Structural study and large magnetocaloric entropy change at room temperature of La1?x□xMnO3 compounds
【24h】

Structural study and large magnetocaloric entropy change at room temperature of La1?x□xMnO3 compounds

机译：La1 x□XmnO3化合物室温下的结构研究和大磁热熵变化

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In this study, our central focus is to investigate the magnetocaloric characteristics of a La _(1? x ) □ _( x ) MnO _(3) ( x = 0.1, 0.2 and 0.3) series prepared by a sol–gel technique published in Prog. Mater. Sci. , 93 , 2018, 112–232. The crystallographic study revealed that our compounds crystallize in a rhombohedral structure with R c . Ferromagnetic (FM) and paramagnetic (PM) characters were detected from the variation in magnetization as a function of magnetic fields at different temperatures. The second order transition was verified from the Arrott plots ( M ~(2) vs. ( μ _(0) H / M )), where the slopes have a positive value. In order to verify the second order, we traced the variation of magnetization vs. temperature at different magnetic fields for x = 0.2. This revealed a ferromagnetic (FM)–paramagnetic (PM) transition when temperature increases. Relying on the indirect method while using the Maxwell formula, we determined the variation in the entropy (?Δ S _(M) ) as a function of temperature for different magnetic fields for the three samples. We note that all the studied systems stand as good candidates for magnetic refrigeration with relative cooling power (RCP) values of around 131.4, 83.38 and 57.26 J kg ~(?1) with magnetic fields below 2 T, respectively. Subsequently, the magnetocaloric effect was investigated by a phenomenological model for x = 0.2. The extracted data confirm that this phenomenological model is appropriate for the prediction of magnetocaloric properties. The study also demonstrated that this La _(0.8) □ _(0.2) MnO _(3) system exhibits a universal behaviour.
机译：在这项研究中，我们的中枢重点是研究通过发布的溶胶 - 凝胶技术制备的La _（1×x）□_（x）MnO _（3）（x = 0.1,0.2和0.3）系列的磁热传输特性在prog。母娘。 SCI。 ，93,2018,112-232。结晶研究表明，我们的化合物在具有R C的菱形结构中结晶。从不同温度下的磁场的函数中检测到铁磁性（FM）和顺磁性（PM）字符。从Arrott图（M〜（2）Vs.（μ_（0）H / m））验证了二阶转换，其中斜率具有正值。为了验证二阶，我们跟踪了X = 0.2的不同磁场处的磁化与温度的变化。当温度升高时，这揭示了铁磁性（FM） - 抗磁性（PM）过渡。使用Maxwell公式的同时依赖间接方法，我们确定了熵（ΔS_（m）的变化作为三个样本的不同磁场的温度的函数。我们注意到，所有研究的系统都符合具有相对冷却功率（RCP）值的磁性制冷的良好候选者，其中距离2 T的磁场分别为约131.4,83.38和57.26J kg〜（？1）。随后，通过X = 0.2的现象学模型研究了磁热效应。提取的数据确认该现象学模型适用于预测磁热性质。该研究还证明，该LA _（0.8）□_（0.2）MnO _（3）系统表现出普遍行为。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号