Photocatalytic Degradation of Pollutants by Using Highly Surface Pd Doped on ZnO/CdS Nanocomposite: As a Model of Water Treatment

In the last few decades, more attention has been focussed on water treatment. In this study, an advanced catalyst Pd-doped ZnO-CdS nanocomposite was prepared using the photo deposition method. The structure and morphology of the obtained material were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), examining optical properties using UV-visible spectroscopy. Results of absorption show broader bands with moderated energy band gaps and improved photocatalytic properties. The photocatalytic applications show that the increase in amount of pd/ZnO-CdS nanocomposites up to 0.4 g/L increase the number of active site, but beyond 0.4 g/L there is little increase in % degradation. Therefore, the best catalyst at 0.4 g/L was used to remove BG dye. Photo catalytic activity increase was observed for Pd/ZnO-CdS nanocomposites which is about 86.6%. Photocatalytic degradation efficiency (PDE%) increases as the dye concentration decreases from 86.66% to 26.9 %. It was observed that the photo-catalytic degradation of BG dye was 86.6%-95.8% for the first four cycles. This indicates the good stability of ZnO-CdS/Pd nano-composites and could be potentially applied in the practical batch degradation.