Codoped g-C3N4 nanosheet for degradation of organic pollutants from oily wastewater

Abstract

Removal of dye pigments from oily waste water is one of the challenges for paint industries. Thus the present work is focused on developing efficient photocatalyst based on gC3N4 to degrade Rhodamine B (RhB) dye from oily water. In order to enhance the photocatalytic activity low concentration of B and Ag was doped and codoped in gC3N4 by facile methods. XRD and XPS results showed that B is doped in gC3N4 matrix by replacing C while metallic Ag nanoparticles are decorated on gC3N4 sheet-like morphology as confirmed from TEM images. The maximum narrowing of band gap to 2.55 eV was achieved upon codoping with Ag and B as estimated from UV–Vis spectra. As observed by emission spectra, both B and Ag effectively reduces the recombination process by trapping the photogenerated charges and fast transfer of electron from gC3N4 to Ag. The maximum surface area is also recorded for Ag-B-codoped gC3N4. Improvising all three factors namely surface area, visible light absorption, and charge separation in Ag-B-codoped gC3N4 creates synergic effect to increase the photocatalytic RhB degradation rate by 4.2 times as compared to undoped gC3N4. Codoped gC3N4 also displayed significantly higher photo-degradation performance than Ag or B monodoped gC3N4.