Aligned channel Gelatin@nanoGraphite aerogel supported form-stable phase change materials for solar-thermal energy conversion and storage

To overcome the poor shape stability, low thermal conductivity, and weak photo response of phase change materials (PCMs), we designed a kind of Gelatin@nanoGraphite aerogel with aligned channel structure of graphite nanosheets and a new type of stable Paraffin/Gelatin@nanoGraphite composite PCMs was fabricated in this work. The graphite nanosheets were used as thermal conduction and photon absorption fillers. The microstructure, thermal conductivity, thermal stability, and solar-thermal conversion of the composite PCMs have been investigated. The results show that the rich porosity of the prepared Gelatin@nanoGraphite aerogel effectively loads a large amount of paraffin wax (>93.2 wt%). Meanwhile, the composite PCMs had anisotropic solar-thermal conversion and thermal conductivity (radial 3.75 and axial 2.59 W/(m·K)), high melting enthalpy (>146.4 J/g), and excellent phase change cycle and shape stability. This material has intensive application prospects in the fields of building energy saving, human body hyperthermia and solar energy collection system.