An efficient visible-light photocatalyst prepared from g-C3N4 and polyvinyl chloride

A facile method has been developed to prepare an efficient visible-light photocatalyst using g-C3N4 and ordinary polyvinyl chloride (PVC) as main precursors. Firstly, g-C3N4 was dispersed into PVC solution with tetrahydrofuran as solvent. Secondly, the above suspension containing g-C3N4 was heated at 50 °C to obtain PVC/g-C3N4 composite via solvent volatilization. Finally, the product was heated at 150 °C for 2 h to obtain the photocatalyst covered by a small amount of conjugated polymer derived from PVC via dehydrochlorination reaction. The as-prepared photocatalyst was characterized by Scanning electron microscopy, UV–vis diffuse reflectance spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman Spectroscopy, photoluminescence spectroscopy, etc. The photocatalytic activity of the as-prepared photocatalyst was evaluated by photodegradation of Rhodamine B solution under visible-light irradiation. The results show that the conjugated polymer can obviously improve the absorbance of g-C3N4 in the visible light range and the BET specific surface area, and hardly affect its crystalline structure. The visible-light photocatalytic activity of the as-prepared photocatalyt is much higher than that of pure g-C3N4, and increases first and then decreases as the content of conjugated polymer on the photocatalyst surface increases. The visible-light photocatalytic mechanism has been discussed.