In this paper, we report a novel and simple method to prepare shape-stabilized phase change energy storage materials (PCM). Graphene oxide (GO) is an amphiphile with hydrophilic edges and a hydrophobic basal plane. GO can act as an emulsifier to create highly stable oil-in-water (O/W) Pickering emulsions. The microspheres of phase change material (hexadecanol) with graphene oxide were realized by Pickering emulsion templating. The size of microspheres can be tuned by pH, the concentration of GO and shear rate. The morphology of the microspheres was observed by scanning electron microscopy (SEM). GO sheets were found coated on the surface of hexadecanol. The leakage tests indicate that no leakage occurs when 6% GO is added. The thermal properties of microcapsules were studied using differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and Thermal cycling tests. DSC results indicate that with the addition of GO, the melting enthalpy decreases. The decrease is ∼6.9 % in the case of ∼6 % GO content. The encapsulated phase change material has good thermal stability, owing to the existence of graphene oxide on the surface protecting the hexadecanol from leakage. This shape-stabilized phase change materials may have potential applications in energy storage.

In this paper, we report a novel and simple method to prepare shape-stabilized phase change energy storage materials (PCM). Graphene oxide (GO) is an amphiphile with hydrophilic edges and a hydrophobic basal plane. GO can act as an emulsifier to create highly stable oil-in-water (O/W) Pickering emulsions. The microspheres of phase change material (hexadecanol) with graphene oxide were realized by Pickering emulsion templating. The size of microspheres can be tuned by pH, the concentration of GO and shear rate. The morphology of the microspheres was observed by scanning electron microscopy (SEM). GO sheets were found coated on the surface of hexadecanol. The leakage tests indicate that no leakage occurs when 6% GO is added. The thermal properties of microcapsules were studied using differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and Thermal cycling tests. DSC results indicate that with the addition of GO, the melting enthalpy decreases. The decrease is ∼6.9 % in the case of ∼6 % GO content. The encapsulated phase change material has good thermal stability, owing to the existence of graphene oxide on the surface protecting the hexadecanol from leakage. This shape-stabilized phase change materials may have potential applications in energy storage.