A carbon nitride/TiO2 nanotube array heterojunction visible-light photocatalyst: synthesis, characterization, and photoelectrochemical properties

A carbon nitride/TiO2 nanotube array (CN/TNT) heterojunction photocatalyst with visible-light response was prepared by a simple electrochemical method. The photocatalyst was characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). The photoelectrochemical properties and photocatalytic activities of the obtained-samples were systematically tested under visible light irradiation. The activity of heterojunction photocatalyst CN/TNTs is higher than that of TNTs. The obviously increased performance of CN/TNTs is ascribed mainly to enhancement of electron–hole separations both at the interface and in the semiconductors.