Enhanced photocatalytic activity of metal oxides/[beta]-cyclodextrin nanocomposites for decoloration of Rhodamine B dye under solar light irradiation

We present the photocatalytic decoloration of Rhodamine B (RhB) dye with the nanocomposites such as TiO2, ZnO, TiO2/[beta]-cyclodextrin ([beta]-CD) and ZnO/[beta]-CD. Band gap energy of nanocomposites was calculated by UV-DRS analysis and the results showed that the band gap energy of ZnO/[beta]-CD nanocomposite is lower than that of other catalysts. The microstructures of the nanocomposites have been characterized by PXRD and FE-SEM analyses. The results showed that crystallinity and surface morphology of metal oxides (MO) (say, TiO2 and ZnO) are not changed in MO/[beta]-CD nanocomposite systems. GC-MS results showed that the photocatalytic decoloration of RhB follows the steps such as N-deethylation, cleavage of chromophore and mineralization of dye.