Harvesting thermal energy with green-synthesised copper oxide / silver nanocomposites

This study focuses on the green synthesis of copper oxide/silver nanocomposites (CuO/Ag NCs) utilising weeping willow leaf extract, highlighting its application in enhancing solar thermal energy conversion. Nanocomposite Synthesis was confirmed via UV-Vis spectroscopy, which showed characteristic absorption peaks between 220–370 nm, and further validated by X-ray diffraction, scanning electron microscopy, transmission electron microscope analyses, which confirmed the crystalline nature and spherical morphology of the nanoparticles, with a size range of 40–70 nm. The Energy-dispersive X-ray spectroscopy analysis verified the existence of Ag, Cu, and O elements in the created nanocomposites. Photothermal application results demonstrated a significant temperature increase of nanofluid systems under solar irradiation. The temperatures rose from 27°C–43°C within one hour, promote an improvement in thermal absorption efficiency. These findings suggest that the synthesised CuO/Ag NCs are effective in solar energy applications, providing a foundation for environmentally friendly solar thermal technologies.