Enhanced photocatalytic performance of boron and phosphorous co-doped graphitic carbon nitride nanosheets for removal of organic pollutants

In this work, the photocatalytic activity of graphitic carbon nitride is improved by co-doping of non-metal elements and morphologic regulation. We introduce B and P elements into the carbon nitride skeleton and meanwhile decrease the thickness by a thermal etching route. The obtained B, P co-doped nanosheets (BPCNNS) has narrow bandgap (2.61 eV) to utilize more visible light, and its ultrathin morphology promotes the separation and migration ability of photo-generated charges. Accordingly, the BPCNNS sample shows enhanced photocatalytic activity for removal of Oxytetracycline (OTC) and Rhodamine B (RhB) in comparison with the un-doped, single element doped and co-doped bulk samples. ∼70% OTC was removed after 120 min and RhB was completely decomposed in 60 min under visible light irradiation by the BPCNNS photocatalyst. Furthermore, the high cycling reusability and stability of the BPCNNS photocatalyst are demonstrated. This work suggests the activity of graphitic carbon nitride can be synergistically enhanced by introducing multiple dopants and morphologic control. Also, it provides a potential photocatalyst to efficiently purify wastewater containing different organic pollutants.