Photothermal Water Evaporation via Hollow-CuS Embedded PDMS Sponge Under UV, Visible, and IR Irradiation

Photothermally-based solar steam generation has emerged as a promising solution for efficient water evaporation. Photothermal particles offer significant advantages in water treatment by converting light energy into heat. While gold nanoparticles (AuNPs) are commonly used, their cost can be prohibitive. This study focuses on developing a photothermal water evaporation matrix using hollow CuS nanoparticles (NPs)-embedded in a polydimethylsiloxane sponge. This innovative approach enhanced both water absorption and heat transfer. The system achieved a remarkably high water evaporation rate of 3.23 kg/m 2 h under xenon arc lamp irradiation. The investigation revealed that specific wavelength ranges, particularly the ultraviolet (UV) and infrared regions, significantly contribute to water evaporation, with the UV region playing the most prominent role. These findings help optimize photothermal effects by enhancing light absorption at specific wavelengths. Notably, CuS NPs offer a cost-effective alternative to AuNPs.