• Journal of the Korean Applied Science and Technology
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• v.27 no.4
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• pp.487-493
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• 2010

There has been a controversy on the formation mechanism of $TiO_2$ nanotubes. This study was conducted to elucidate the formation mechanism of $TiO_2$ nanotubes. $TiO_2$ nanotubes were prepared by a hydrothermal method. $TiO_2$ nanotubes formation mechanism was investigated by controlling the formation time. It was found that $TiO_2$ nanotubes were formed by growing, not by wrapping of sheets. The phase structure of hydrogen titanate nanotubes was different from that of $TiO_2$ nanotubes. It is important to wash the sodium titanate nanotubes with an acidic solution to get hydrogen titanate nanotubes and then to calcine the hydrogen titanate nanotubes around $400^{\circ}C$ to obtain $TiO_2$ nanotubes.

• Journal of Powder Materials
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• v.24 no.4
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• pp.279-284
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• 2017

The formation mechanism and photocatalytic properties of a multiwalled carbon nanotube (MWCNT)/$TiO_2$-based nanotube (TNTs) composite are investigated. The CNT/TNT composite is synthesized via a solution chemical route. It is confirmed that this 1-D nanotube composite has a core-shell nanotubular structure, where the TNT surrounds the CNT core. The photocatalytic activity investigated based on the methylene blue degradation test is superior to that of with pure TNT. The CNTs play two important roles in enhancing the photocatalytic activity. One is to act as a template to form the core-shell structure while titanate nanosheets are converted into nanotubes. The other is to act as an electron reservoir that facilitates charge separation and electron transfer from the TNT, thus decreasing the electron-hole recombination efficiency.

• Applied Chemistry for Engineering
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• v.32 no.3
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• pp.243-252
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• 2021

With increasingly strict requirements for advanced energy storage devices in electric vehicles (EVs) and stationary energy storage systems (EES), the development of lithium-ion batteries (LIBs) with high power density and safety has become an urgent task. Because the performance of LIBs is determined primarily by the physicochemical characteristics of its electrode material, TiO₂, owing to its excellent stability, high safety levels, and environmentally friendly properties, has received significant attention as an alternative material for the replacement of commercial carbon-based anode materials. In particular, self-organized TiO₂ micro and nanostructures prepared by anodization have been intensively investigated as promising anode materials. In this review, the mechanism for the formation of anodic TiO₂ nanotubes and microcones and the parameters that influence their morphology are described. Furthermore, recent developments in anodic TiO₂-based composites as anode electrodes for LIBs to overcome the limitations of low conductivity and specific capacity are summarized.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.375-382
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• 2017

In the present review, we provide an overview of the research trend of anodic $TiO_2$ nanostructures. To date, most anodic $TiO_2$ nanostructure formation has focused on the fluoride ion electrolyte system to form nanotube layers. Recently, a novel approach that describes the formation of thick, self-organized $TiO_2$ nanostructures was reported. These layers can be prepared on Ti metal by anodization in a hot organic/$K_2HPO_4$ electrolyte. This nanostructure consists of a strongly interlinked network of nanosized $TiO_2$, and thus provides a considerably higher specific surface area than that of using anodic $TiO_2$ nanotubes. This review describes the formation mechanism and novel properties of the new nanostructures, and introduces potential applications.

• The Journal of the Korean dental association
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• v.48 no.2
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• pp.106-112
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• 2010

Tissue engineering has been enhanced by advance in biomaterial nature, surface structure and design. In this paper, I report specifically vertically aligned titania ($TiO_2$) nanotube surface structuring for optimization of titanium implants utilizing nanotechnology. The formation, mechanism, characteristics of titania nanotubes are explained and emerging critical role in tissue engineering and regenerative medicine is reviewed. The main focus of this paper is on the unique 3 dimensional tubular shaped nanostructure of titania and its effects on creating epochal impacts on cell behavior. Particularly, I discuss how different cells cultured on titania nanotube are adhered, proliferated, differentiated and showed phenotypic functionality compared to those cultured on flat titanium. As a matter of fact, the presence of titania nanotube surface structuring on titanium for dental applications had an important effect improving the proliferation and mineralization of osteoblasts in vitro, and enhancing the bone bonding strength with rabbit tibia over conventional titanium implants in vivo. The nano-features of titania nanotubular structure are expected to be advantageous in regulating many positive cell and tissue responses for various tissue engineering and regenerative medicine applications.