Preparation and Phase Change Performance of Graphene Oxide and Silica Composite Na2SO4·10H2O Phase Change Materials (PCMs) as Thermal Energy Storage Materials

In this study, a novel nucleating agent composed of graphene oxide (GO) and silicon dioxide (SiO2) (GO–SiO2) is developed. GO is used as a skeleton material through which SiO2 nanomaterials are absorbed and subsequently incorporated into Na2SO4·10H2O phase change materials (PCMs). Furthermore, this study examines the phase change performance of the composite Na2SO4·10H2O materials. Fourier-transform infrared (FTIR) spectra confirmed the physical combination of GO with a SiO2 nanoparticles. Scanning electron microscope (SEM) results showed that the GO–SiO2 composite exhibited a layered structure and excellent dispersibility. The GO–SiO2 composite Na2SO4·10H2O PCMs displayed a low level of supercooling, i.e., about 1.2 °C with the addition of GO–SiO2 at 2.45 wt%. This was because the synergistic relation of the GO and the high dispersion SiO2, imparted more nucleation sites for Na2SO4·10H2O. Additionally, the prepared PCMs achieved high phase change latent heat and thermal conductivity, even under these conditions. The results show that the GO–SiO2 in the Na2SO4·10H2O exhibited advantageous application prospects for the improvement of the thermal performance of hydrate salts