Green Synthesized TiO2-SnO2 Nanocomposite for the Photocatalytic Degradation of Methylene Blue Dye

Abstract

TiO₂-SnO₂ nanocomposite was prepared by green synthesis method with the help of the Allium sativum extract obtained from garlic cloves. The green synthesized TiO₂-SnO₂ nanocomposite was characterized by XRD, SEM, EDS, Raman, ATR-FTIR, and UV-Visible spectroscopy. The XRD pattern reveals the polycrystalline nature of the synthesized nanocomposite and indicates the simultaneous presence of anatase and rutile phases of TiO₂, along with SnO₂. The calculated average crystallite size is 11.79 nm. The SEM images give the concept of surface morphologies of the synthesized nanocomposite. EDS spectrum detects the presence of Ti, Sn, and O in the synthesized nanocomposite material. The Raman spectrum confirms the chemical compositions. ATR-FTIR spectrum shows the presence of organic components of garlic as functional groups in the synthesized nanocomposite. The Tauc plot obtained from the UV-Visible spectral data displays the direct and indirect band gap values of 3.97 and 3.25 eV, respectively. Moreover, the present study investigates the effect of the synthesized nanocomposite’s concentration on the photocatalytic degradation of methylene blue (MB) dye. The aqueous suspension of TiO₂-SnO₂ nanocomposite photocatalyst with a concentration of 1.5 mg/mL exhibits maximum photocatalytic activity.