Preparation and characterization of expanded dickite/decanoic acid composite phase change materials

The leakage of phase change materials presents a significant challenge that impedes their application. Loading porous materials onto phase change materials is an effective approach to address this issue. In this study, a porous expanded dickite as a carrier was utilized to load decanoic acid and create a composite phase change material. The loading content of decanoic acid was varied to obtain different composite phase change materials. FTIR analysis confirmed the formation of hydrogen bonds between the expanded dickite carrier and decanoic acid. SEM images and EDS mapping results demonstrated that decanoic acid was evenly dispersed on the expanded dickite carrier without any agglomeration. The expanded dickite carrier effectively immobilized the decanoic acid through hydrogen bonding, thereby preventing leakage, as long as the loading content of decanoic acid did not exceed 60%. The higher thermal conductivity of the expanded dickite carrier promoted the thermal conductivity of the expanded dickite/decanoic acid composite phase change materials, enhancing the responsiveness of the composite phase change materials to ambient temperature. The composite phase change material containing 60 wt% decanoic acid exhibited excellent endothermic/exothermic cycle stability, and after six cycles, its latent heat remained stable.