Preparation and Thermal Performance of Silica/n-Tetradecane Microencapsulated Phase Change Material for Cold Energy Storage

A novel silica (SiO2)/n-tetradecane microencapsulated phase change material (MEPCM) was synthesized by in situ interfacial polycondensation. The influences of the amount of the composite emulsifier and the mass ratio of n-tetradecane and tetraethyl silicate on the MEPCM performance were systematically investigated. The morphology, chemical structure, and composition of the MEPCM were characterized by scanning electron microscopy and energy dispersive X-ray spectrometer, Fourier transform infrared spectroscopy, and X-ray diffraction, and its thermal performance and thermal stability were measured by differential scanning calorimetry and thermogravimetric analysis. The results showed that the n-tetradecane core material was successfully encapsulated by silica shell material with encapsulation ratio of 62.04%. The MEPCM had a melting enthalpy of 140.5 kJ kg–1 and thermal conductivity of 0.139 W m–1 K–1. Because of its excellent thermal performance and thermal stability, silica/n-tetradecane MEPCM displays a good potential for cold energy storage.