1：Experimental Design and Method Selection:

The study involved synthesizing Ag-GNS using a one-step reduction method with GO, sodium citrate, and AgNO3, and then preparing Ag-GNS/PEG composites by mixing with PEG under ultrasonication and vacuum drying. Methods included FT-IR, XRD, Raman spectroscopy, SEM, TEM, XPS, UV-Vis absorption, thermal conductivity measurements, DSC, TGA, and shape-stability tests.

2：Sample Selection and Data Sources:

Materials used were silver nitrate, graphite flakes, sodium citrate, polyethylene glycol (PEG, Mn = 6000), and other analytical-grade reagents. Samples included pure PEG, GNS/PEG, and Ag-GNS/PEG composites with varying Ag-GNS content (2-8 wt%).

3：List of Experimental Equipment and Materials:

Equipment included FTIR-460 spectrophotometer, X Pert Powder XRD, DXR Microscope for Raman, FEI Nova Nano SEM 450 for SEM, ESCA-LAB250 for XPS, HITACHI U-4100 spectrophotometer for UV-Vis, DRE-III tester for thermal conductivity, TA Instruments Universal Analysis 2000 for DSC and TGA, hot stage, digital camera, tablet press, solar simulator, and temperature recorders.

4：Experimental Procedures and Operational Workflow:

Synthesis of GO via modified Hummers' method, reduction to Ag-GNS or GNS, mixing with molten PEG, ultrasonication, vacuum evaporation, drying. Characterization involved spectral and microscopic analyses, thermal property measurements, and photothermal conversion tests under solar radiation.

5：Data Analysis Methods:

Data were analyzed using standard techniques for each instrument, including calculation of solar-to-thermal energy storage efficiency using the provided equation, and statistical comparisons of thermal properties.