Review on recent advances in shape-stable phase change hydrogels for thermal energy storage applications

The escalating global energy demand, coupled with the intensifying energy crisis, has catalyzed significant interest in the pursuit of efficient and stable energy storage technologies. In this context, shape-stable phase change hydrogels are considered as a promising class of materials for thermal energy storage (TES) applications. This review first introduces phase change hydrogels and elucidates the basic mechanism of their phase change. Recent advances in the preparation strategies of phase change hydrogels, such as chemical cross-linking, physical cross-linking and interpenetrating polymer network methods, are comprehensively reviewed and it is assessed how these methods affect the performance characteristics of the hydrogels. In addition, the article focuses on various applications of phase change hydrogels in thermal management, highlighting their role in improving energy efficiency in buildings, regulating the temperature of wearable devices and facilitating infrared thermal management. This review aims to provide a valuable reference for future research endeavors and practical implementations in TES.