Thermal Property Enhancement and Encapsulation Technologies for Phase Change Materials: A Review of Nanofillers, Porous Scaffolds, and Application-Oriented Strategies

Abstract

Phase change materials offer high latent heat and isothermal operation, yet their real-world use is consistently blocked by low thermal conduction, melt leakage, and—for inorganic types—subcooling and segregation. Here this paper systematically benchmark three nanofiller families (carbon, metal, and ceramic) and three porous scaffold types (metal foam, carbon skeleton, and ceramic skeleton) in terms of thermal performance enhancement, thermal capacity retention, cycling durability, and economic cost. Carbon fillers give the largest conductivity jumps but consume latent heat; ceramic fillers keep capacity intact with only moderate conduction gains; scaffolds stop leakage effectively but impose distinct penalties in weight, strength, or manufacturing complexity. This paper also identify five obstacles that prevent these composites from reaching industry, suggest selection rules for different applications, and outline priorities for affordable synthesis, durable encapsulation, and system-level optimization.