The role of the g-C3N4 precursor on the P doping using HCCP as a source of phosphorus

This work describes the doping of graphitic carbon nitride (g-C3N4) with phosphorus performed by 2-h heat treatment of a mechanical mixture of g-C3N4 precursor (urea, dicyandiamide, and guanidine hydrochloride) with hexachlorocyclotriphosphazene at 525 degrees C. The amount of fixed phosphorus in the resulting g-C3N4 structure reached approximately 10 wt% in the case of the urea precursor. For the other two precursors, the fixed phosphorus content in the final products was less than 5 wt%. Several experimental techniques (SEM, XRFS, TG, XRD, FTIR, physisorption of nitrogen, UV-VIS DRS, PL spectroscopy, and electrochemical analysis) were used to characterize the prepared samples. The photodegradation activity of the samples was determined by degradation of Rhodamine B under irradiation with visible light (420 nm). In general, the photodegradation activity of the samples was dependent on the phosphorus content. The highest photodegradation activity was obtained for urea-based g-C3N4 doped with the lowest phosphorus content, with a threefold increase in calcination product yield. The mechanism of incorporation of phosphorus into the final g-C3N4 structure was explained as a two-phase process. (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC

Automated summary

This study describes the doping of graphitic carbon nitride (g-C3N4) with phosphorus through heat treatment, and investigates the influence of phosphorus content on the photocatalytic degradation activity.