Graphene oxide–nano‐titania composites for efficient photocatalytic degradation of indigo carmine

Nano‐titania composites assembled with variable weight percentages (wt%) of graphene oxide (GO) were synthesized, and their effectiveness as photocatalysts was investigated for the degradation of indigo carmine under visible light irradiation. Controlled hydrolysis of titanium tetrachloride (TiCl 4 ) was performed in aqueous medium, and 1% aqueous solution of GO was added under ultrasonication. Depending on the wt% of GO, the materials were designated as 1, 2, 5, 10, 15 wt%GO–nano‐titania (GO–NT) composites. Their morphology and structural properties were characterized using X‐ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (UV–vis DRS), high‐resolution transmission electron microscopy (HRTEM), and field‐emission scanning electron microscopy (FE‐SEM). Excellent photocatalytic activity was demonstrated by the NT composite containing 10%GO in 60 min, and the required optimum conditions were established.