MXene-wrapped bio-based pomelo peel foam/polyethylene glycol composite phase change material with enhanced light-to-thermal conversion efficiency, thermal energy storage capability and thermal conductivity

Abstract Phase change materials (PCMs) have attracted great interest from researchers and have been widely developed in the field of solar thermal energy storage. Herein, a novel bio-based pomelo peel foam (PPF)/polyethylene glycol (PEG) composite PCM was designed and prepared via the simple impregnation process, which is further modified with low loading of MXene nanosheets for the purpose of improving its light-to-thermal conversion efficiency, thermal energy storage capability and thermal conductivity. With the incorporation of MXene nanosheets into PPF, the light-to-thermal conversion efficiency was improved obviously, the loading of PEG in form-stable composites phase change materials (FCPCMs) increased from 86.9 wt% (FCPCM-1) to 96.2 wt% (FCPCM-2, FCPCM-3 and FCPCM-4), and the thermal conductivity of obtained PPF@MXene/PEG FCPCMs was also improved (from 0.25 W/mK to 0.42 W/mK). It shows that the obtained PPF@MXene/PEG FCPCMs can be fully utilized in the field of solar thermal energy storage.