Silica-confined composite form-stable phase change materials: a review

Solid–liquid phase change materials (PCMs) are a kind of important heat energy storage materials that can store/release great amounts of latent heat at a specific temperature or within a narrow temperature range and thus can be applied in a lot of fields related to heat energy storage or thermal management. However, their practical applications are still limited due to formidable challenges such as the risk of leakage, easy phase separation and low thermal conductivity, etc. Silica possesses the merits of cheap, high chemical and physical stability, flame retardancy and relatively high thermal conductivity. It can be applied as both shell material and supporting materials to obtain form-stable PCMs and thus address the aforementioned challenges. In this review, the recent progresses of silica-based form-stable PCMs were summarized. We introduced the main methods for the preparation of the silica-confined composite form-stable PCMs at first. Then, the physical and chemical properties of the reported silica-confined composite form-stable PCMs were summarized and discussed. Finally, some emerging research topics and challenges on silica-based composite form-stable PCMs are proposed.