Abstract:
In today’s world, global problems such as a shortage of fossil fuel energy, environmental pollution, and global warming are becoming increasingly serious. For the development of human society, sustainability is particularly important. Energy is the basis for human survival and promotes the development of human society. However, rapid growth in population and the global economy has led to a significant increase in energy demand. At the same time, extensive use of fossil fuels has polluted the environment and led to a shortage of fossil energy. Currently, with the continuous increase in energy consumption and development of human society, there is a pressing need to develop energy storage technology. Latent heat storage, using phase change materials that play a vital role in the field of energy storage, has been widely accepted as an effective way to improve heat energy utilization. Phase change materials provide a type of thermal energy storage that can store a large amount of latent heat through physical phase change. This heat is then released in a controlled manner within a small temperature change based on thermal energy requirements. At present, phase change materials have important applications in aerospace, industrial and agricultural production, building materials, energy and power, textile materials, highway transportation, and engine technology. Most current research on phase change materials focuses on medium- and low-temperature materials, especially those materials whose phase change temperature is lower than 100 ℃. There is less research on high-temperature phase change materials owing to the encapsulation and corrosion of such materials. The problem of performance is difficult to solve, yet high temperature phase change materials are in urgent need in some extreme high temperature environments. High-temperature phase change materials (HTPCM) can control thermal energy under extremely high temperatures. They have important prospects for application in the fields of thermal protection and thermal management in high-temperature environments such as aerospace, solar energy, etc. The microencapsulation of phase change materials can solve the problem of melt exudation of these materials during the phase change process, improve the environmental adaptability of these materials, and expand their applications. This article mainly reviewed the preparation and application of HTPCM above 300 ℃. The classification of phase change materials, the method of synthesis of microcapsules, and the preparation of high temperature microcapsules were discussed. Through research, it is found that fluoride microcapsules, with their high melting point and enthalpy value, are a promising material in the field of HTPCMs.