Reusable water filtration system: Multifunctional Ag/CeO₂/g-C₃N₄ nanocomposite for photocatalytic dye degradation and solar-driven water desalination

The Ag/CeO 2 /g-C 3 N 4 nanocatalyst is proposed to enhance photocatalytic performance and photothermal efficiency for water purification applications through synergistic interactions among its components. The nanocomposite (NC) was simply prepared by the solution-based impregnation method followed by calcination. Characterization techniques confirmed the formation of the heterostructure and its distinct optical properties. The photocatalytic degradation of methylene blue (MB) and photothermal water desalination were evaluated under controlled conditions. The Ag/CeO 2 /g-C 3 N 4 nanocatalyst accomplished a high decomposition of MB (99%) within 20 min, significantly outperforming individual components. The incorporation of silver nanoparticles (NPs) improved light absorbance and facilitated effective charge separation, enhancing the photocatalytic performance. In photothermal desalination, the composite produced desalinated water with 0 ppm of metals and 0 CFU/mL for heterotrophic plate count (HPC) bacteria. These results demonstrate the composite’s potential as an efficient, cost-effective, and environmentally friendly alternative for sustainable water purification technologies.