The photocatalytic activity of TiO₂ is enhanced by the addition of β-cyclodextrin (β-CD) on decoloration of azocarmine G (AZG) dye under solar light irradiation. The morphologies, phase structures and optical properties of TiO₂ and TiO₂-β-CD catalysts has been investigated by FE-SEM, PXRD and UV–visible DRS respectively. The interaction between AZG dye and β-CD has also been characterized by UV-visible and FT-IR spectral analyses. The TiO₂–β-CD system exists higher photocatalytic activity than pure TiO₂ system. This is attributed to their large surface area, absorption enhancement in solar light region and effective separation of electrons and holes. The percentage removal (~98%) was achieved at acidic pH within 120 minutes. The observed results indicate that decolorization of the AZG dye follows pseudofirst-order kinetics.
Keywords: Azocarmine G dye; TiO2; β-CD; Photocatalytic decoloration