Preparation of GO/TiO₂ composite photocatalyst and treatment of synthetic dye wastewater

Abstract

A series of composite photocatalysts were prepared by using graphene oxide (GO) and TiO2 hydrogel. The composite photocatalyst was characterized through SEM, XRD and Raman spectroscopy, the decolorization effect of pure TiO2 and composite photocatalyst on methylene blue (MB) dye wastewater under different experimental conditions was studied. The results show that TiO2 in composite photocatalyst is mainly anatase phase and its photocatalytic activity is better than pure TiO2. When the addition of GO reaches 15%(mass fraction), the photocatalytic activity is the highest. When 250mg composite photocatalyst is added to 30mL synthetic wastewater with a concentration of 10mg/L and an initial pH value of about 8, the decolorization rate can reach 93.1% after 2.5 hours, and the composite photocatalyst has visible photocatalytic activity. It is presumed that the photogenerated charges of GO/TiO2 composite photocatalyst may directly destroy the luminescent groups in the MB molecule,and no other new luminescent groups are generated during the treatment.

Keywords

• go-tio₂
• photocatalytic activity
• methylene blue
• ultraviolet light