| Because of its wide theoretical significance and practical application, nano-structure array has attracted wide attention. The existed research shows that TiO2 nanotubes array present much better photoelectric performance, photocatalytic and sensing properties, compared to any other form of titania, due to their large high surface-to-volume ration, highly ordered, vertically oriented and size dependent properties. Electrochemical self-assembly, based on the anodization, is a simple, variable and effective method for preparation nanotubes array.In the past several years, highly-ordered vertically oriented nanotubes array fabricated by simple anodization on Ti. Especially, the microstructure, the diameter and the length of such oxide nanotubes in highly-ordered array, so far, can be controlled by varying anodization parameters including the applied potential, concentration, pH value of electrolytes, anodization time, and cooperation of cathode. However, little attention was paid to the anode, and the influence of anode materials was not researched systematically. The important question is:how can the alloy elements be doped into the nanotube? In this thesis, we choose different Ti alloys as anodes, and study the influence of the phase, alloy elements and shape to nanotubes array during the anodization. The biological properity and wettability of the Ti surface covered nanotubes array were studied.We find a special coaxial bimodal nanotubes array, firstly, by anodization biomedical titanium alloy materials, named TLM. The external diameter of coaxial bimodal outer nanotube is about 140 nm; and a inner tube about 90 nm, hole size about 40 nm. This coaxial bimodal feature is also obvious. Coaxial nanotubes array may possess considerable advantages such as larger surface area, easy to collect and control, and special coaxial double tubes structure. It is a promising candidate for a wide range of applications, such as solar cells, gas-sensor, and other nano electrical devices with critical feature for these devices to reach their ultimate efficiency limits. The conditions of the formation of the coaxial structure were found. By compared, the TiO2 film prepared on TLM after soaked in SBF 3 days, adhesion ratio of osteoblast on which obviously higher than on the same conditions of Ti, the cell shape very perfect. The anodization of TLM can on second improve the biocompatibility and bioactivity of TLM, offer the qualification the nonage cicatrisation of plant materials.We studied the effect of the Ti alloy phase to the nanotubes array during the anodization?,?and?+?alloys. The Ti samples were heated above the phase transition point, followed by air, water or liquid nitrogen quenching to?-phase,?-phase or (?+?)-phase. There were nanotubes with rough surface and high surface-to-volume ration, when the pure titanium, which was quickly liquid nitrogen quenched, was anodized. The ratios of?-phase and?-phase in TLM and TC21 alloys were controlled by different heat treatments, respectively. We obtained the nanoporous, nanotube, and coaxial bimodal nanotube three kinds of array on nearly?-phase and (?+?)-phase TLM alloy. Through anodiazion TC21 alloy, we find that the interface of?-phase and?-phase would affect the nanotubes in uniform. The quickly annealing treatment quenching would be a great benefit to TiO2 nanotube phase-transition.Six kinds of TiNb alloys, with different composition rations, were anodized. From the results, we find that Nb can be doped into the TiO2 lattice. The quantity contained of Nb will be helpful to the growth of the nanotube. We obtain two-sized anodic oxide nanotubes at the Ti47Nb alloy surface in 1 mol/L H2SO4 and 0.25 wt % NH4F solution, and highly ordered structure with small nanotube connected by nano wire in ethylene glycol containing 0.25 wt % NH4F and 2.0% deionized water. Mechanistic of the Self-Organization Process for coaxial bimodal nanotubes array formation on Ti alloys was advanced.The importance of the coaxial nanotubes array is also the method of control of the structural feature. Far more, by modifying the composition of alloy, anodization time and the potential, different components, properties, and size of coaxial nanotubes array layer will be formed.The array of vertically aligned titanium oxide nanowires and nanotubes were grown on the surface of microporous titanium substrate. A annealed treatment with 550?to make them more crystallization. In contrast to common titanium foil electrode, the nanowires array was obtained. The nanowires array structure of titania on the microscale porous substrate combined with the stable rutile structure contributes to super-hydrophobic and super-oleophilic properties. This material can be used effectively for the separation of oil and water and is a feasible alternative to current separation methods. A possible mechanism has also been presented. |
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