Fe₃O₄–graphene/polyethylene glycol–SiO₂ as a phase change material for thermal energy storage

Renewable energy efficiency can be increased using phase change materials (PCMs). This study has successfully developed PCMs with supporting materials, such as SiO₂, Fe₃O_4, and graphene. Briefly, the synthesis of Fe₃O₄–Graphene/polyethylene glycol (PEG)–SiO₂ begins with the synthesis of Fe₃O₄–Graphene using the coprecipitation method. Next, Fe₃O₄–Graphene/PEG–SiO₂ nanocomposites are prepared with Fe₃O₄–Graphene mass varied in a range of 5%–8%. Based on the results, the Eg value of the Fe₃O₄–Graphene is 1.73 eV. The morphology of Fe₃O₄–Graphene/PEG–SiO₂ shows that Fe₃O₄ particles stick to the surface of the graphene sheet. The addition of Fe₃O₄–Graphene mass affects the saturation magnetization value, which increases with an increase in Fe₃O₄–Graphene within the range of 1.05–2.55 emu/g. In addition, the latent calorific value obtained by differential scanning calorimetry shows that all the samples have a phase transition range within a temperature range of 59.4°C-60.5 °C and a latent calorific value of >100 J/g. Owing to its high latent calorific value, Fe₃O₄–Graphene/PEG–SiO₂ can be applied as a heat-storage material.