$$\hbox {C}₃\hbox {N}₄$$ supported on chitosan for simple and easy recovery of visible light active efficient photocatalysts

To investigate the photocatalytic activities of heterogeneous systems under visible light, graphitic carbon nitride (g-(hbox {C}₃hbox {N}₄)) and chitosan (CS) were chosen as a model system. By solution cast method, (hbox {C}₃hbox {N}₄) were embedded into a CS biopolymer matrix in this study. The purpose is to degrade methyl orange (MO) using a novel (hbox {C}₃hbox {N}₄)/CS nanocomposite thin film. Using a visible light-equipped photoreactor with a tungsten incandescent lamp, photo-decolourization of dye was carried out. To catalyse the photodegradation of organic dye pollutant MO, a (hbox {C}₃hbox {N}₄)/CS nanocomposite film photocatalyst was found to be successful and a recovery of 100% of the photocatalyst is achieved by a simple new hand-picking technique. Using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform-infrared spectroscopy and UV–visible diffuse reflectance spectroscopy, detailed characterization was carried out. (hbox {C}₃hbox {N}₄)/CS has high capacity and better photocatalytic activity compared to g-(hbox {C}₃hbox {N}₄) and CS, because (hbox {C}₃hbox {N}₄) possesses a larger surface area and CS has high absorption efficiency which is indicated by the photocatalytic discolouration of MO under visible light irradiation. The (hbox {C}₃hbox {N}₄)/CS nanocomposite thin film photocatalyst is regarded as an excellent catalyst with 98% degradation efficiency and is prepared by the simple solution cast method. The total organic carbon value was measured to be 86%. These values evidence that the mineralization of MO was carried out under these conditions.