CdSe-sensitized TiO2 nanotube array film fabricated by ultrasonic-assisted electrochemical deposition and subsequently wrapped with TiO2 thin layer for the visible light photoelectrocatalysis

Abstract

A composite structure, TiO2 nanotube array/CdSe nanoparticle/TiO2 layer, was fabricated by inserting CdSe nanoparticles into anodized TiO2 nanotube arrays via ultrasonic-assisted cyclic voltammetry electrochemical deposition and subsequently wrapped by a TiO2 thin layer via TiCl4 hydrolysis. The films were characterized by X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectroscopy and UV–vis diffuse reflectance spectroscopy. For the film used as the photoanode, linear sweep voltammetry and transient photocurrent were investigated in a three-electrode system under visible light illumination. And the photocatalytic activity was evaluated by the oxidation of glucose in the supporting electrolyte at different potential bias under visible light illumination. The results showed that CdSe nanoparticles are prone to disperse into the nanotube arrays via cyclic voltammetry electrochemical deposition under ultrasonic condition. Increasing cyclic voltammetry cycle increases the loading of CdSe on the TiO2 nanotube arrays. The CdSe-sensitized TiO2 nanotube array films exhibit a wide-absorption response in the visible light region. The TiO2 nanotube array/CdSe/TiO2 film, prepared by ultrasonic-assisted electrochemical deposition with 50cyclic voltammetry cycles and subsequently coating a TiO2 thin layer, exhibits better protection against photocorrosion of CdSe. The TiO2NTA/CdSe/TiO2 film possesses visible light photoelectrocatalytic activity on the degradation of glucose.