SiO2 aerogel is a synthetic ultralight material with a very high pore volume and a large internal surface area.The latent heat storage of PCM is considered as having tremendous potential due to its high energy storage density and thermal storage at a constant to near constant temperature associated with the phase transition temperature.We combine SiO2 aerogel with PCM to improve the ability of heat accumulation.SiO2 aerogel is selected as matrix material and Li2CO3-Na2CO3(Li2CO3∶Na2CO3=2∶3)eutectic saltis selected as phase change material.SiO2 aerogel doped with phase change material can be obtained via sol-gel, aging and supercritical drying method.Phase-transition temperature of Li2CO3-Na2CO3 eutectic salt within SiO2 aerogel is 499.1 ℃ and latent heat is 365.5 J/g.Its structure and propertyare characterized by scanning electron microscopy(SEM), thermogravimetric analysis (TGA), x-ray diffraction(XRD), fourier transform infrared spectroscopy(FTIR).In order to prevent phase change material from leakage.SiO2is chosen to encapsulate phase change material by using interfacial polymerization and perfect core-shell structure of phase change microcapsule isobtained (fig.2).Phase change microcapsule will be doped into SiO2 aerogel in the following research.