Photocatalytic activity enhancement of modified g-C3N4 by ionothermal copolymerization

Abstract

The chemical structure and morphology of g-C3N4 were controlled. Dicyandiamide and barbituric acid were used as a co-precursor to graft aromatic groups in the tri-s-triazine structure unit and form the delocalized π-conjugate system. Meanwhile, lithium chloride and potassium chloride were used as heating media to restrain the agglomeration and keep the layered structure of the products. The results show that the as-prepared photocatalysts have a (C3N4)x–(C7N7)y structure. According to the images by scanning electron microscopy (SEM) and transimisson electron microscopy (TEM) a clearly lamellar structure of the photocatalysts appears when the amount of barbituric acid is <0.86 g. The specific surface area can be increased by the ionothermal copolymerization synthesis method. Compared to g-C3N4-550, BA-CN4 has a greater photocatalytic ability. The as-prepared photocalyst has a good degradation ratio after 4-run degradation of RhB dye recycle experiment.