Enhanced Photocatalytic Degradation of Water Pollutants Using Au/CdS: TiO<sub>2</sub> Films Nanocomposites under Ultra Violet-Visible Irradiation

In this work, Au/ CdS: TiO2 film nanocomposites were prepared and deposited on a glass substrate for photocatalytic application. First, sol-gel dip coating thin films of CdS: TiO2 were synthesized. Next, the plasma sputtering technique was used to deposit Au on the CdS: TiO2 thin films. Composite CdS: TiO2 ratios were (1:1, 1:0.25, and 1:0.5). The produced films were studied using X-ray diffraction (XRD) measurements, atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), and UV-visible spectroscopy. With the addition of TiO2, the energy band gap, as measured by UV-visible spectroscopy, decreased from 3.82 eV for pure Au:CdS to 3.76 eV with increasing TiO2. To evaluate the photocatalytic activity of pure Au/CdS and modified Au/CdS:TiO2 thin films, methylene red (MR) aqueous solution degradation was used. The outcomes showed that after just 50 minutes, Au/CdS (1): TiO2(1) had an effective photocatalytic activity of up to 57.95%.