Novel microencapsulated ternary eutectic alloy-based phase change material

Recent applications of phase change materials (PCMs) include energy storage, transportation, and management. Multicomponent PCMs represent a primary tool for regulating operating temperatures across a broad range to accommodate diverse requirements across various temperature ranges. Moreover, the microencapsulation of PCMs promotes their manageability and functionality. However, microencapsulated PCMs (MEPCMs) with ternary eutectic alloy systems are yet to be reported. Moreover, various technical challenges impede the integration of components during PCM fabrication. In this study, a core–shell-type MEPCM with a ternary eutectic Al–Cu–Si alloy system was successfully developed for the first time. The MEPCM was prepared over two simple steps: (1) the formation of a precursor shell on the PCM particles using boehmite treatment and (2) the heat oxidation treatment to form a stable oxide shell. The fabricated MEPCM exhibited a melting point of 517 °C and a latent heat of 353 J g−1. MEPCMs operating at this temperature have not previously been reported. Furthermore, the heat storage density of the fabricated MEPCM was significantly higher than that of other reported MEPCMs. Additionally, the fabricated MEPCM exhibited high durability under 100 cycles of heat storage and release tests, retaining >90 % of its latent heat capacity. Therefore, for the first time, this study successfully developed a core–shell-type MEPCM with a ternary eutectic system.