Tungsten (VI) oxide and titanium dioxide doping with gold nanocluster (Au NCs) for photocatalytic enhancement in methylene blue photodegradation

Research was aimed to synthesize gold nanoclusters-doped tungsten oxide (Au NCs/ WO₃) and titanium dioxide (Au NCs/ TiO₂) for application as photocatalyst in methylene blue degradation. Synthesis of materials was performed by Au NCs preparation by using HAuCl₄ with glutathione for then was doped to WO₃ and TiO₂. Materials were characterized using Fourier-Transform infrared (FTIR) spectrophotometry, x-ray diffraction and scanning electromagnetic analyses. Physicochemical characterization revelead that the Au NC/WO₃ has irregular form with the large pore gap and the x-ray diffraction pattern exhibited anatase formation for Au NCs/ TiO₂ but there is no specific peak identified for Au NCs/ WO₃ in the composite. FTIR analysis suggests that the formation of doping-support interaction was occurred. The presence of Photocatalytic activity of both materials was compared for methylene blue photodegradation. Kinetics study of the degradation suggest that methylene blue photodegradation obeys pseudo-second order kinetics, and it is noted that the doping enhanced the degradation efficiency of TiO₂ from 83.71to 93.71 %, and from 36.32 to 49.87% for WO₃.