Thermal energy storage property and temperature control performance of phase change materials eutectic mixture nanocomposite

The utilization of high-performance phase change materials (PCMs) that can reversibly store thermal energy is of immense interest and strategy for effective energy conservation and management. In this work, a new PCM nanocomposite, consisting of a eutectic mixture of stearic acid and n-nonadecane as core and SiO2 as shell, was prepared by direct impregnation method. Additionally, a laboratory scaled test room was designed to investigate the intelligent temperature control function of the nanocomposite in building materials. The optimized nanocomposite was characterized using Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques. The DSC data demonstrated that the PCMs eutectic mixture content in the stearic acid- n-nonadecane–SiO2 nanocomposite was 52.8 wt.% and the melting temperatures and latent heats of stearic acid - n-nonadecane eutectic mixture and optimized nanocomposite were 45.1 and 44.0 °C, and 163.7 and 86.5 J/g, respectively. Furthermore, the accelerated thermal cycling test confirmed the excellent thermal cycling stability of the nanocomposite after 500 heating-cooling cycles. Moreover, the laboratory scaled test room results showed that the incorporation of the resulting nanocomposite in the gypsum could reduce indoor temperature fluctuation, and the performance was improved with the increase in the mass percentage of the nanocomposite in the gypsum composite. The obtained nanocomposite had good thermal reliability and temperature control performance and thus can be a promising candidate for hi-tech applications in intelligent temperature control and precise thermal management.