Low-cost, thermo-conductive, hydrophobic, and shape-stabilized porous carbonized watermelon peel embedded phase-change materials for solar-energy-saving and conversion

摘要

The traditional phase change materials (PCMs) exhibited leakage problems, poor thermal conductivity, low solarthermal conversion ability, and high cost. Therefore, a low-cost shape-stabilized composite PCM was prepared by impregnating n-Eicosane into the carbonized watermelon peel (CWP) coated with manganese oxide (MnO2) nanosheets (MnO2@CWP). The prepared MnO2@CWP-C20 composite PCMs have a good shape-stability, high thermal-conductivity (0.58 W/m K), high phase-change enthalpy (220 J/g), high energy conversion/storage efficiency (94.5%), outstanding cycle stability, hydrophobicity, and self-cleaning properties. The shape-stabilized MnO2@CWP-C20 composites PCMs not only provide a simple approach for the efficient utilization of solar energy but also expand the applications of low-cost biomass waste, thanks to their exceptional features.