TiO2 Sensitized by Natural Dye Extracted from Cinnamon Bark for Photodegradation of Methylene Blue in Water Under LED Irradiation

This study utilizes natural-dye-sensitized photocatalysts (NDSPs) as cost-effective and ecologically safe materials for photocatalytic degradation of organic contaminants such as methylene blue (MB). A natural dye extracted from cinnamon powder has been established to sensitize TiO2, effectively creating a visible sunlight-driven photocatalyst. The sensitization of TiO2 by cinnamon extract was confirmed by Fourier transform infrared spectroscopy (FTIR). There was no change in the phase and morphology of TiO2 after sensitization. The enhancement of light absorbance in the visible region of TiO2 after being sensitized by cinnamon was confirmed by UV–visible diffused reflectance spectroscopy (DRS). The photocatalytic removal of methylene blue by cinnamon-sensitized TiO2 (TiO2-CI) was optimized by studying the impact of different factors (irradiation time, photocatalyst amount, pH, light power, and starting concentration of MB). Efficient removal of 87