重稀土HRENiGa_(2)(HRE=Dy,Ho或Er)化合物的优异低温磁热性能  

Excellent cryogenic magnetocaloric properties in heavy rare-earth based HRENiGa_(2)(HRE=Dy,Ho,or Er)compounds

作　　者：郭丹 Luis M.Moreno-Ramírez Jia-Yan Law 张义坤 Victorino Franco Dan Guo;Luis M.Moreno-Ramírez;Jia-Yan Law;Yikun Zhang;Victorino Franco(Key Laboratory of Novel Materials for Sensor of Zhejiang Province&School of Electronics and Information Engineering,Hangzhou Dianzi University,Hangzhou 310012,China;Departamento de Física de la Materia Condensada,ICMS-CSIC,Universidad de Sevilla,P.O.Box 1065.41080-Sevilla,Spain;State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China)

机构地区：[1]Key Laboratory of Novel Materials for Sensor of Zhejiang Province&School of Electronics and Information Engineering,Hangzhou Dianzi University,Hangzhou 310012,China [2]Departamento de Física de la Materia Condensada,ICMS-CSIC,Universidad de Sevilla,P.O.Box 1065.41080-Sevilla,Spain [3]State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China

出　　处：《Science China Materials》2023年第1期249-256,共8页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China(52071197);the Science and Technology Commission of Shanghai Municipality(19ZR1418300 and 19DZ2270200);the Independent Research and Development Project of State Key Laboratory of Advanced Special Steel,Shanghai Key Laboratory of Advanced Ferrometallurgy,Shanghai University(SKLASS 2021-Z05);Grant PID2019105720RB-I00 funded by MCIN/AEI/10.13039/501100011033,US/JUNTA/FEDER-UE(US-1260179);Consejería de Economía,Conocimiento,Empresas y Universidad de la Junta de Andalucía(P18-RT-746);the support provided by China Scholarship Council(CSC)of the Ministry of Education,China(202006890050)。

摘　　要：RENiX_(2)化合物(其中RE为稀土元素,X为p区元素)在低温磁制冷应用中受到高度关注.它们根据元素的不同可以结晶成CeNiSi_(2)型、NdNiGa_(2)型或MgCuAl_(2)型晶体结构,并表现出不同类型的磁有序性从而影响其磁性.MgCuAl_(2)型铝化物由于具有有利的铁磁基态从而表现出比CeNiSi_(2)型硅化物和NdNiGa_(2)型镓化物更大的磁热性能.此外,RENiGa_(2)镓化物根据RE元素的不同可以结晶成NdNiGa_(2)或MgCu Al_(2)型结构.本文中,我们选择重稀土(HRE)元素来探索HRENiGa_(2)(HRE=Dy,Ho或Er)镓化物的微观结构、磁有序和磁热性能.三种化合物均以MgCuAl_(2)型晶体结构结晶,并且随着温度的升高经历了从铁磁到顺磁的二级磁相转变.DyNiGa_(2),HoNiGa_(2)和ErNiGa_(2)化合物的最大等温磁熵变(|ΔSisomax|)值分别为6.2,10.4和11.4 J kg^(-1)K^(-1)(0-5T),这与许多最近报道的低温磁制冷材料性能相当.特别地,HoNiGa_(2)和ErNiGa_(2)化合物(包括它们的复合材料)在氢气液化的温度范围内表现出优异的磁热性能.RENiX_(2)compounds,where RE=rare-earth element and X=p-block element,have been highly regarded for cryogenic magnetocaloric applications.Depending on the elements,they can crystallize in CeNiSi_(2)-type,NdNiGa_(2)-type,or MgCuAl_(2)-type crystal structures,showing different types of magnetic ordering and thus affect their magnetic properties.Regarding the magnetocaloric effect,MgCuAl_(2)-type aluminides show larger values than those of the CeNiSi_(2)-type silicides and the NdNiGa_(2)-type gallides due to the favored ferromagnetic ground state.However,RENiGa_(2)gallides can crystallize in either NdNiGa_(2)-or MgCuAl_(2)-type structures depending on the RE element.In this work,we select heavy RE(HRE)elements for exploring the microstructure,magnetic ordering and magnetocaloric performance of HRENiGa_(2)(HRE=Dy,Ho or Er)gallides.They all crystallize in the desired MgCuAl_(2)-type crystal structure which undergoes a second-order transition from ferro-to para-magnetic state with increasing temperature.The maximum isothermal entropy change(|ΔSisomax|)values are 6.2,10.4,and11.4 J kg^(-1)K^(-1)(0-5 T)for DyNiGa_(2),HoNiGa_(2),and ErNiGa_(2),respectively,which are comparable to many recently reported cryogenic magnetocaloric materials.Particularly,the excellent magnetocaloric properties of HoNiGa_(2)and ErNiGa_(2)compounds,including their composite,fall in the temperature range that enables them for the in-demand hydrogen liquefaction systems.

关 键 词：重稀土 磁热性能 晶体结构 磁制冷材料 稀土元素 磁有序 等温磁熵变 硅化物 

分 类 号：TQ133.3[化学工程—无机化工]