Graphene-nickel/n-carboxylic acids composites as form-stable phase change materials for thermal energy storage

Superoleophilic graphene-nickel foam (PDMS-G-NF), which was prepared by coating graphene nanosheets onto nickel foam followed by surface modification with polydimethylsiloxane (PDMS), was used as porous supporting material to prepare form-stable phase change materials (PCMs) composites. Owing to the strong hydrophobic and superhydrophilic wettability of PDMS-G-NF, PCMs can be absorbed spontaneously into PDMS-G-NF and can stay stable without leakage even over their melting points. The incorporation of PCMs into PDMS-G-NF does not change the crystal structure but lowers the crystallinity size of PCMs in the composites, which is confirmed by X-ray powder diffraction (XRD) analysis. The latent heat of PDMS-G-NF/PCM composites was measured in the range of 42.3-123.41 kJ kg−1. Taking advantages of the simple process and good stability the PDMS-G-NF should be ideal candidates as an alternative to traditional PCMs, which may have great potentials for renewable energy saving applications.