Graphene-based phase-change composites for thermal energy storage, conversion, and applications

Phase-change materials (PCMs) are essential for advancing clean energy technologies and enhancing energy efficiency. However, pure PCMs have problems such as leakage, low thermal conductivity, and poor light absorption, limiting their effectiveness in thermal energy storage and conversion. To overcome these challenges, phase-change composites (PCCs) have been developed by combining PCMs with various other materials. This approach addresses the shortcomings of pure PCMs and leverages the strengths of each component, offering considerable practical and research potential. Graphene nanomaterials, with their high in-plane thermal conductivity, easy assembly, low density, and good light-absorption properties, are particularly promising for enhancing the overall properties of PCMs. Graphene-based PCCs exhibit notable advantages over pure PCMs, including enhanced thermal conductivity, higher phase enthalpy retention, versatile energy absorption and conversion, and better encapsulation capabilities. This article reviews recent advancements in the preparation methods, thermal properties, and energy conversion applications of graphene-based PCCs. It integrates theoretical insights, numerical analyses, and experimental findings while also exploring future research directions and potential multifunctional applications in thermal energy storage, transfer, and conversion.