Photocatalytic Degradation of Methyl Orange with Commercial Organic Pigment Sensitized TiO2

In this paper, TiO2 photocatalyst sensitized with commercial organic pigment, C.I. Pigment Yellow 154 (PY) or C.I. Pigment Red 254 (PR) was prepared by solvothermal method, respectively. Photocatalytic activities of the as- prepared pigment/TiO2 composites was evaluated by the degradation of the methyl orange (MO) under visible light irradiation. Microstructural, morphological, and optical properties of the as-prepared pigment/TiO2 composites were characterized by X-ray diffraction technique (XRD), BET surface area analysis, UV–vis diffuse reflectance spectrum (UV–vis DRS). Results displayed that the as-prepared pigment/TiO2 composites have high visible light photocatalytic activity and stability. The TOF of pigment/TiO2 based on the content of pigment had nearly loss when the photocatalyst was used four times. The remarkable enhancement in the visible light photocatalytic activities of the pigment/TiO2 heterostructures could be attributed to the effective electron–hole separations at the interfaces of the two semiconductors.