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In this study, one-dimensional titanium dioxide (TiO${}_2)$ nanotube arrays (NTAs) with different tube lengths are synthesized via anodic oxidation of Ti foils and their ultraviolet (UV) light detection properties are investigated to determine their optimum growth conditions. A TiO₂ nanotube ultraviolet photodetector based on photoelectrochemical cell is fabricated using the optimum TiO₂ nanotubes and its characteristics in the ultraviolet region are determined. The photodetector is examined under a UV illumination intensity of 10mW/cm²and at a wavelength of 368nm. Its responsivity is measured to be about 96$\mu$A/cm² and its response time is less than 0.2s under an applied bias of 0.5V.

“Multi-layer” walled TiO₂ nanotube array has been prepared by anodization with post-treatment of ethanol. Two post-treatment methods, which were ethanol and water treatment respectively, exerted a marked and different effect on the structure of nanotube. With ethanol immersion, the “multi-layer” walled nanotube can be obtained, while water treatment cannot produce the “multi-layer” walled structure. The main reason could be the uptake of carbon and fluoride during anodization process. Compared with “single-layer” walled TiO₂ nanotube, “multi-layer” walled TiO₂ nanotube demonstrated higher photocatalytic activity.

Sodium-ion batteries (SIBs) have received widespread attention because of their scalability, low cost, and environmental advantages. Whereas, the low capacity and disappointing cycle capability of anode materials are unavoidable challenges, and high-capacity electrodes are accompanied by large volume expansion and cycle decay. Herein, self-supported TiO₂ nanotube array nanocomposites are rationally designed by combining the stability of TiO₂ and the high capacity of $P$. The unique nanotube structure can effectively limit the expansion of phosphorus so that this anode has excellent reversibility and cycling. It affords a reversible capacity of 0.214 mAh cm${}^{-2}$ at 0.08 mA cm${}^{-2}$, a rate capability of 0.146 mAh cm${}^{-2}$ at 1.6 mA cm${}^{-2}$, and a stable cycling up to 5000 cycles.

In this study, antibacterial activity and long-lasting release of silver for clinical applications were achieved by utilizing silver nanoparticles on the Titania nanotubes (TNTs) through in situ polymerization of polydopamine (PDA). TNTs were synthesized with the hydrothermal process from Titania nanoparticles. Then the surface modification of TNTs was accomplished by in situ polymerization of PDA and silver ions were reduced on the PDA surface. The feature of obtained samples was characterized using transmission electron microscope (TEM), field emission scanning electron microscope (FESEM), X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR) and atomic absorption spectrophotometry (AAS). The results showed that PDA layer formed on the synthesized anatase TNTs surface. This used as reduction agent for silver ions as well as an adhesive layer to tethering the silver nanoparticles on TNTs surface. AAS results indicated that silver ions reduction to silver nanoparticles on the TNTs surface increased from 3.1 wt.% to 9.6 wt.% in presence of PDA. Also, the results of silver release revealed that PDA worked as an adhesive layer by chelating silver nanoparticles on TNTs and slowing silver ions release rate which implying the possible long-term antibacterial activity of PDA coated TNTs. Besides that, TNTs showed 33% antibacterial activity which is half than silver loaded TNTs-PDA samples. This confirms that PDA have extraordinary effect on the antibacterial activity. This work offers a facile process for the preparation of long-lasting silver based antibacterial activity and facilitates their clinical application in the modern biomedical fields.

Modification of Ti–6Al–4V alloys with silver-loaded TiO₂ nanotubes was investigated. In this study, TiO₂ nanotube (TiNT) was grown on the surface of Ti–6Al–4V plates by means of anodization in an electrolyte solution containing glycerol, water and 0.5wt.% of NH₄F. Silver particles were deposited on TiNT using a Photo-Assisted Deposition (PAD) method. Formation of crystalline phase of TiO₂ on the surface was confirmed by means of XRD while its superficial morphology was observed using FESEM/EDS. Hydrophilicity was assessed by means of contact angle measurement. As-synthesized silver-loaded TiNT on osteoblast ATCC growth in vitro was also investigated in terms of its capacity in supporting osseointegration. The cell viability was determined by MTT (3-[4,5-dimethylthiazol-2yl]-2,5diphenyl-2H-tetrazolium bromide) assay and its differentiation activity was measured by alkaline phosphatase (ALP) assay. The results showed that desposition of silver on TiNT increased cell viability after 14 days culture while improving the hydrophilicity feature. Silver-loaded TiNT on Ti–6Al–4V alloy with Ag precursor concentration of 0.10M showed the optimum viability of osteoblast growth, with 14% improvement in comparison to its unmodified counterpart. The MTT assay showed that no cytotoxicity in vitro was observed on this material. This study provides corroborating evidences that the modification of Ti–6Al–4V alloy may enhance the cell viability and its prominence as dental implant materials.

The anodization with different cathodes (i.e., point cathode, linear cathode or planar cathodes with different areas) was performed to determine the effect of the cathode area on TiO₂ nanotube (TiNT) yield. Results show that proper planar cathode, but not point or linear cathode, is necessary for the production of TiNT, and 8:3 (S_(-)/S₍₊₎) is regarded as the optimal electrode area ratio. The anodization with three electrodes would help to further enhance the unit yield. And the unit yield by one cathode and two anodes is higher than that by two cathodes and one anode, but the product of the latter featured with more uniform structure. Our work would help in guiding the further exploration of high yield TiNT.

This study uses anodic oxidation method for preparation of TiO₂ nanotube for utilization of photocatalyst, and through this seeks to verify creation of TiO₂ nanotube and growth behavior based on the composition of voltage and electrolyte using ethylene glycol as electrolyte. Using commercial titanium (99.9%, 1mm), the contents of NH₄F and H₂O was varied in the course of generating applied voltage, electrolyte, to find out the optimal condition for production. To generate TiO₂ nanotube, ethylene glycol solution with NH₄F and H₂O addition is used as electrolyte. In this experiment, it was confirmed that the electrolyte condition of ethylene glycol + 0.2 wt% NH₄F + 2 vol% H₂O is the optimal condition for generation and growth of TiO₂ nanotube, and that the applied voltage is the important factor for generating nanotube.