摘要
通过溶剂热法合成出了两种稀土簇基金属有机框架材料:{[Ln_7(OH)_8(HOCH_2COO)_8(H_2O)_3]·Cl_5·3H_2O}_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 {[Ln7（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 AH =7 T and compound 2 displays obvious frequency dependence （Hao = 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.
出处
《应用化学》
CSCD
北大核心
2017年第9期1086-1092,共7页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金(21422106
21371144
21431005)资助项目~~
关键词
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
