1：Experimental Design and Method Selection:

The study used a facile impregnation method to prepare composite phase change materials. Polyurethane (PU) was synthesized from polyethylene glycol (PEG) and hexamethylene diisocyanate biuret (HDIB), with ZnO and graphene aerogel (GA) incorporated to enhance properties.

2：Sample Selection and Data Sources:

Materials included PEG (Mn=4000), DMF, L-ascorbic acid, ZnO nanoparticles (30 ± 10 nm), and HDIB. GA was prepared from graphene oxide using a reduction process.

3：List of Experimental Equipment and Materials:

Equipment included Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectrometer (XPS), scanning electron microscopy (SEM), differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), Sun 2000 Solar Simulator (Abet Technologies, USA), optical power meter (Cel-NP 2000, Ceaulight, China), and Keithley power supply. Materials were sourced from Sinopharm Chemical Reagent Co., Ltd., Beijing Chemical Works, Aladdin, and Bayer.

4：Experimental Procedures and Operational Workflow:

GA was fabricated by reducing GO with L-AA, followed by freeze-thaw cycles and drying. Composite PCMs were prepared by mixing PEG, ZnO, and HDIB, then impregnating into GA under vacuum at 80°C for 48 hours. Characterization involved FT-IR, XRD, XPS, SEM, DSC, and TGA. Light-thermal conversion tests used a solar simulator at 100 mW/cm2, and electro-thermal conversion tests used a power supply with copper electrodes.

5：Data Analysis Methods:

Data were analyzed using standard techniques for each instrument; efficiencies were calculated using specific equations for light-thermal and electro-thermal conversion.