Titanium dioxide
Titanium dioxide (TiO2) is biologically stable, non-toxic, and cheap, which makes it a very common semiconductor for dye degradation. Due to its large band gap, some alterations can be made to improve its photocatalytic abilities such as the synthesis of 6,13-pentacenequinone/ TiO2. Titanium dioxide in conjunction with ultraviolet light can be utilized for the decolorization and detoxification of diluted colored water waste such as Alizarin, azo dyes, methyl red, methylene blue, etc. Reduced graphene oxide-TiO2 can act as photocatalyst for the degradation of methyl orange, azo-dye, and pharmaceutical water waste.