Facile preparation of a TiO2 quantum dot/graphitic carbon nitride heterojunction with highly efficient photocatalytic activity.

In this article, mechanical grinding, an effortless and super-effective synthetic strategy, is used to successfully synthesize a TiO2 quantum dot (TiOQD)/graphitic carbon nitride (g-CN) heterostructure. X-ray photoelectron spectroscopy results together with transmission electron microscopy reveal the formation of the TiOQD/g-CN heterostructure with strong interfacial interaction. Because of the advantages of this characteristic, the prepared heterostructure exhibits excellent properties for photocatalytic wastewater treatment. Notably, the optimum photocatalytic activity of the TiOQD/g-CN heterostructure is nearly 3.4 times higher than that of the g-CN nanosheets used for the photodegradation of rhodamine B pollutant. In addition, the stability and possible degradation mechanism of the TiOQD/g-CN heterojunction are studied in detail. This method may stimulate an effective approach to synthesizing QD-sensitized semiconductor materials and facilitate their application in environmental protection.