高导热性氯化钙硝酸钙基水合盐复合相变储能材料的储释热性能

Thermal Storage/Release Properties of Calcium Based(Chloride and Nitrate)Salt Composite Phase Change Materials with High Thermal Conductiviti

以六水氯化钙和四水硝酸钙的混合盐为基体材料,并使用亲水性改性膨胀石墨为骨架材料,通过熔融混合制备水合盐相变材料。采用非均匀成核方法在膨胀石墨(EG)表面包覆一层亲水性Al_(2)O_(3)膜,采用浸渍法制备了CaCl_(2)·6H_(2)O-Ca(NO_(3))_(2)·4H_(2)O/EG水合盐复合相变材料。利用扫描电镜(SEM)、X射线粉晶衍射仪(XRD)、红外光谱(FTIR)、差示扫描量热仪、导热系数分析仪、储释热循环实验对复合相变材料的储能性能及稳定性进行研究。结果表明,复合相变材料导热性能显著提高,是纯基体材料的6.5倍。同时,200次循环实验结果表明复合相变材料具有良好的稳定性。

A hydrated salt phase change material was synthetized by melting and mixing method,among which calcium chloride hexahydrate as a main material and calcium nitrate tetrahydrate as an auxiliary material.A hydrophilic Al2O3 film was coated on the surface of expanded graphite(EG)based on the heterogeneous nucleation method,and the composite phase change material named CaCl_(2)·6H_(2)O-Ca(NO_(3))_(2)·4H_(2)O/EG was produced by impregnation method.According to the scanning electron microscopy(SEM),X-ray diffraction(XRD),Infrared spectroscopy(FTIR),differential scanning calorimeter(DSC),thermal conductivity analyzer and thermal cycling experiment,the energy storage properties and the stability of composite phase change material were systematically studied.The composite phase change material has significantly improved thermal conductivity,which is 6.5 times higher than that of the monomeric material.Meanwhile,the results of 200 cycles test attest that the composite phase change material has fabulous stability.