Enhanced properties of mica-based composite phase change materials for thermal energy storage

Abstract

Abstract Emerging composite phase change materials were synthesized from KH-550-decorated mica (Md) and polyethylene glycol (PEG) by vacuum impregnation method. Expanded graphite (EG) was added to synergistically improve the thermal conductivity and thermal storage capacity and to prepare Md/EG/PEG composite phase change material. The structure morphology and energy storage performance of composite PCMs were studied by X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), nitrogen gas adsorption-desorption isotherms, thermogravimetric (TG), and differential scanning calorimetry (DSC). The good thermal stability of the prepared Md/EG/PEG was proved by TG analysis and leakage testing. The addition of EG not only enhanced the thermal conductivity but also increased the thermal storage capacity of the composite PCMs. Compared with pure PEG, the thermal conductivity of Md/EG/PEG was increased by 107.4%, and the latent heat of Md/EG/PEG was 136.3 J g−1. Infrared imaging indicated that Md/EG/PEG was more sensitive to temperature changes and respond quickly. These results demonstrated that Md/EG/PEG has potential in building energy conservation.