Exploring flame-retardant, shape-stabilized multi-functional composite phase change materials

In recent years, the issue of fossil energy depletion has become increasingly prominent. Phase change materials (PCMs), as a state-of-the-art thermal energy storage technology, have garnered significant attention. Currently, solid-liquid organic PCMs are widely utilized in various applications. However, pure solid-liquid organic PCMs are prone to leakage and are flammable because of their organic chemical structure, posing a significant risk to human life and property. Consequently, enhancing the flame retardancy of PCMs is imperative. This review highlights recent advancements in the development of multi-functional composite PCMs (CPCMs) with superior thermal and shape stability and enhanced flame retardancy. The flame-retardant mechanisms are elaborated, and the relationship between structure and performance is emphasized. Advanced applications of these CPCMs, including battery thermal management, building materials, flame-retardant textiles, and solar energy conversion, are discussed comprehensively. Finally, this review addresses the existing challenges and future development directions, aiming to inspire further research into flame-retardant PCMs and advance the next generation of multi-functional CPCMs.