Construction of Au/TiO2 Heterojunction with high photocatalytic performances under UVA illumination

Anatase TiO2 nanoparticles (NPs) were successfully prepared through a hydrothermal approach, and Au NPs at various Au (0.1-2 wt%) contents were photodeposited onto the TiO2 NPs surface. The photocatalytic efficiency for the Au/TiO2 NPs for resorcinol photodegradation throughout UVA illumination was assessed. The TEM images and XPS findings indicated that the Au NPs are highly distributed onto TiO2 surface in the metallic state. The 0.1%Au/TiO2 NPs exhibited the highest photocatalytic efficiency of about 95.34%; however, 72.36% is given by pure TiO2 NPs. It was found that the photodegradation rate of 0.1% Au/TiO2 NPs exhibited 1.5 times of magnitude higher than pure TiO2 NPs. 0.1%Au/TiO2 NPs was considered to be the outstanding photoactive due to the ultimate efficient charge-carriers separation through charge transfer between Au and TiO2 NPs. The Au NPs sizes, its dispersity on TiO2 surface and surface plasmon resonance (SPR) were believed the critical factors for the higher photocatalytic performance of 0.1% Au/TiO2 NPs. The prepared photocatalysts are found to be the promising materials for toxic organic compounds remediation and solar conversion.