A review on synthesis, characterization and application of nanoencapsulated phase change materials for thermal energy storage systems

Nanoencapsulated phase change materials (NEPCMs) are expected to be one of the most potential energy storage materials. After years of research and development, a mature and huge microencapsulated phase change material (MEPCM) industry has been built in terms of both synthetic technology and practical application. However, microcapsules also have its limitations, such as low heat transfer efficiency, high breakage rate and so on. In order to solve these problems, NEPCMs are being successfully developed. In this review, the research background and development process of NEPCMs were introduced. The structure, principle and function of NEPCMs, including the types and selection principles of core and shell materials were analyzed. Besides, almost all of the common nanoencapsulation methods were presented, some of the methods were emphatically introduced such as in-situ polymerization, interfacial polymerization, emulsion polymerization, miniemulsion polymerization, suspension polymerization and sol–gel method. Furthermore, the thermal properties, physical properties and chemical properties of nanocapsules were discussed and analyzed. Finally, the applications of nanocapsules in building, textile, slurry, solar energy and food industry were summarized. This study was devoted to PCM, nanoencapsulation methods, characterization and application prospects.