硬脂酸/二氧化硅复合相变储热材料制备及性能研究

Study on the preparation and performance of stearic acid/SiO_2 composite phase-change thermal energy storage materials

采用“溶胶-凝胶”工艺制备出具有不同硬脂酸质量分数的硬脂酸/二氧化硅复合相变储热材料,运用SEM、XRD和DSC等手段对复合相变储热材料的结构与性能进行了表征和测试。复合相变储热材料是硬脂酸嵌入到二氧化硅三维纳米网孔中形成的,其相变温度和相变潜热均随硬脂酸质量分数的增加而增大,且相变温度低于纯硬脂酸,相变潜热与对应质量分数下的硬脂酸相当。实验结果表明,硬脂酸/二氧化硅复合相变储热材料具有储热密度大、性能稳定以及导热系数较高等优点。

Stearic acid/SiO2 composite phase-change thermal energy storage materials with different stearic acid mass ratio were prepared by Sol-Gel method, The structure and properties of composites were characterized by SEM, XRD and DSC. It shows that the composites are formed by embedding stearic acid to nano-sized cavity of SiO2 , the melting point and latent heat increase with the increasing of stearic acid mass ratio, and melting point of composites is lower than that of stearic acid, latent heat is equivalent to that of the calculated value based on the stearic acid mass ratio. The composite phase-change thermal energy storage materials have the advantages of high thermal energy storage capacity, large thermal conductivity and steady performance.