Biomass-based shape-stable phase change materials supported by garlic peel-derived porous carbon for thermal energy storage

Phase change materials with low cost, good thermal stability, and excellent shape stability are urgent in energy storage. Herein, a novel shape-stable phase-change material (SSPCM) for thermal energy storage is developed based on activated garlic peel (AGP), derived from widespread and cheap garlic peels. The paraffin (PA)/AGP composite PCM is prepared via vacuum impregnation method. The scanning electron microscope results show that AGP has many grooves, and the pores of AGP are filled by paraffin wax. The specific surface area of AGP is up to 1309 m2/g. The phase change enthalpy in the melting and freezing process is 52.5 J/g and 51.9 J/g, respectively. Moreover, the prepared SSPCM exhibits satisfied shape stability, thermal stability, and waste heat storage ability. Also, the SSPCM has a low latent heat loss rate of about 1.5% after 200 thermal cycles. This work provides an economical and environmental method for synthesizing shape-stabilized phase-change materials based on biomass materials with potential applications in waste heat recovery and recycling.