Enhanced thermal conductivity of polyurethane/wood powder composite phase change materials via incorporating low loading of graphene oxide nanosheets for solar thermal energy storage

To improve the use efficiency and broaden the application fields of PCMs in solar thermal energy storage , the poly (ethylene glycol) (PEG) based polyurethane (PU) /wood powder (WP)/graphene oxide (GO) composite shape-stabilized phase change materials (SSPCMs) with high thermal conductivity were successfully designed and prepared by using PEG as the phase change working substance, WP and GO nanosheets as the supporting matrix, and the GO nanosheets as the thermally conductive filler simultaneously. Scanning electron microscopy (SEM) and X-ray photoemission spectrometer (XPS) reveal that the GO nanosheets were successful deposited on the WP surface via the simple impregnation process. With the increasing content of WP and GO, the thermal conductivity of PU/WP@GO SSPCMs was improved significantly. Meanwhile, the PU/WP@GO SSPCMs not only have excellent thermal properties, including good thermal storage properties, well thermal reliability and reusability and good thermal stability , but also exhibit reliable light-thermal conversion performance. Thus, the obtained novel PU/WP@GO SSPCMs with high thermal conductivity can improve the use efficiency of PCMs as solar light absorber and display a high potential application in the field of solar thermal energy storage.