Hierarchical Encapsulation of Phase Change Materials within Natural Minerals: A Review of 0D to 3D Strategies for Leakage-Free Thermal Energy Storage

Phase change materials (PCMs) have recently attracted considerable attention for their potential applications in thermal energy storage, making the search for suitable supporting materials a critical focus of current PCM research. With their high thermal conductivity, porous structure, and low cost, natural minerals represent a promising alternative to traditional metal and organic supports for PCMs. However, successful encapsulation methods are essential to avoid PCM leakage, frequently demanding surface alteration or the integration of extra functional materials. This review systematically summarizes the microstructure and characteristics of various minerals, while also detailing the corresponding pretreatment and modification techniques. Furthermore, it categorizes the representative encapsulation methods across different dimensions (zero-dimensional nanodots, one-dimensional nanotubes, two-dimensional intercalation and porous adsorption, and three-dimensional aerogels) and their efficacy is extensively discussed. Additionally, the benefits of varied mineral-based PCMs are consolidated, and their utilization in diverse areas including building construction materials, batteries and electronics, solar energy, and asphalt pavements is examined. It provides insights that will aid researchers in understanding recent developments in mineral-based PCMs and in charting future directions.