Photoelectrocatalytic properties of Ag nanoparticles loaded TiO_2 nanotube arrays prepared by pulse current deposition

摘要

A pulse current deposition technique was adopted to construct highly dispersed Ag nanoparticles on TiO_2 nanotube arrays which were prepared by the electrochemical anodization. The morphology, crystallinity, elemental composition, and UV-vis absorption of Ag/TiO_2 nanotube arrays were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and diffuse reflectance spectra (DRS). In particular, the photoelectrochemical properties and photoelectrocatalytic activity under UV light irradiation and the photocatalytic activity under visible light irradiation for newly synthesized Ag/TiO_2 nanotube arrays were investigated. The maximum incident photon to charge carrier efficiency (IPCE) value of Ag/TiO_2 nanotube arrays was 51%, much higher than that of pure TiO_2 nanotube arrays. Ag/TiO_2 nanotube arrays exhibited higher photocatalytic activities than the pure TiO_2 nanotube arrays under both UV and visible light irradiation. The photoelectrocatalytic activity of Ag/TiO_2 nanotube arrays under UV light irradiation was 1.6-fold enhancement compared with pure TiO_2 nanotube arrays. This approach can be used in synthesizing various metal-loaded nanotube arrays materials.