通过溶剂热法合成出了两种稀土簇基金属有机框架材料:{[Ln7(OH)8(HOCH2COO)8(H2O)3]·Cl5·3H2O}n(Ln=Gd(1),Dy(2)). 磁性研究表明,化合物1在低温下具有较大的磁热效应,在3 K、7 T时磁熵变值高达44.4 J/(kg·K),化合物2在不加直流场的情况下具有明显的频率依赖性,表明化合物2具有缓慢弛豫的性质. 此外,粉末衍射结果发现,化合物1和2具有非常高的化学稳定性,其可稳定存在于pH值1~14的水溶液及沸水中. 结果表明,稀土簇基金属有机框架材料在低温磁制冷方面具有潜在的利用价值.
Two lanthanide cluster-based metal-organic frameworks of {[Gd7(OH)8(HOCH2COO)8(H2O)3]·Cl5·3H2O}n(Ln=Gd(1), Dy(2)) were obtained by solvothermal reaction.The magnetic studies indicate that compound 1 exhibits a large magnetocalotic effect(MCE) values of 44.4 J/(kg·K) at 2 K and ΔH=7 T and compound 2 displays obvious frequency dependence(Hdc=0) which suggests that compound 2 shows slow relaxation.In addition, the results of powder diffraction reveals that compounds 1 and 2 display very high chemical stability, which can be stable in acid/base solution of pH=1~14 and boiling water.These results indicate that the lanthanide cluster-based metal-organic frameworks have the potential application in the low-temperature refrigeration.
郑秀英;孔祥建;龙腊生;郑兰荪
厦门大学化学化工学院,固体表面物理化学国家重点实验室,能源材料化学协同创新中心 福建 厦门 361005
化学化工
稀土金属有机框架;磁热效应;频率依赖性;化学稳定性
lanthanide organic-metal frameworks;magnetocalotic effect;frequency dependence;chemical stability
《应用化学》 2017 (009)
1086-1092 / 7
国家自然科学基金(21422106,21371144,21431005)资助项目Supported by the National Natural Science Foundation of China(No.21422106, No.21371144, No.21431005)
10.11944/j.issn.1000-0518.2017.09.170176
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