Preparation And Functionalization Of Composite Nanotube Arrays On The Surface Of Ti-based Alloys

Due to highly ordered arrays and large specific surface area, TiO₂-basednanotube arrays have a wide use in photoelectric and photocatalysis field.Because energy in visible light region accounts for43%of total solar energy, ithas a important sense to prepare a kind of catalysis material that can make fulluse of visible light. TiO₂-MoO3composite nanotubes and TiO₂-MoO3-SnO2composite nanotubes were prepared by anodic oxidation method on the surface ofTi-15wt%Mo alloy and Ti-15wt%Mo-7wt%Sn alloy in this article. Then, the twokinds of nanotubes were calcined at different temperature, after that, the sampleswere loaded with gold nanoparticles by impregnation-sediment method, and theas-prerared samples have had visible light response. The surface morphology,composition, phase, photoelectric properties and visible light catalytic propertiesof nanotubes were characterized and tested by scanning electronmicroscope（SEM）, energy dispersive spectrometer（EDS）, X-raydiffraction（XRD）, photovoltaic system and self-organizing photo degradationdevice.In visible light region, properties of light absorption of Ti-15%Monanotubes and Ti-15%Mo-7%Sn nanotubes which were calcined were enhancedthan those of anodic oxidation samples. When nanotubes were calcined at600℃,the photoelectric properties of two kinds of nanotubes were the best. Accordingto the ultra violet–visible diffuse reflection spectrum（U-V DRS）, loaded withgold nanoparticles, samples had a big red shift, at the same time, properties ofoptical absorption were strengthened in visible light region. When Ti-15%Monanotubes were calcined at600℃, it had the best property, reaching to5.8%, theefficiency reached to6.4%when Ti-15%Mo nanotubes（600℃） were loaded at80℃. When Ti-15%Mo-7%Sn nanotubes were calcined at400℃, it had thehighest efficiency, reaching to5.5%, the efficiency reached to9.1%whenTi-15%Mo-7%Sn nanotubes（400℃） were loaded at80℃. Compared to TiO₂nanotubes（400℃）, Ti-15%Mo nanotubes（400℃） and Ti-15%Mo-7%Snnanotubes（400℃） had a great red shift, and property of light absorption of Ti-15%Mo-7%Sn nanotubes（400℃） was the best. It verified that joining Mo（Sn）element to Ti had enhanced nanotubes property of light absorption.