Design of a solar-driven TiO 2 nanofilm on Ti foil by self-structure modifications

Pringle

Corr

et al. 2017

An environmentally friendly electrolyte for the synthesis of titanium dioxide nanotubes by anodization is presented. Plasma treatment of de‐ionized water produces some important reactive species such as nitrate and hydrogen peroxide. This plasma‐treated water serves as an efficient electrolyte in the formation of titanium dioxide nanotubes during anodization. In order to further understand the roles of nitrate and hydrogen peroxide, titanium foil was anodized in plasma treated water containing nitrate or/and hydrogen peroxide as well as in its equivalent solution made by adding nitric acid and/or hydrogen peroxide to water. It was found that the plasma treated water containing both nitrate and hydrogen peroxide produced more uniform arrays of highly crystalline titanium dioxide nanotubes than produced in the aqueous solution made with nitric acid and hydrogen peroxide.

{N O}_{3}^{-}

Section: Resultsmentioning

confidence: 99%

{N O}_{3}^{-}

), produced by the dissociation of nitric acid during the anodization, formed a soluble complex with Ti and lead to the formation of the porous TiO 2 tubular structure.…”

Section: Introductionmentioning

confidence: 99%

Superior performance of plasma treated water as an anodizing electrolyte for producing nanoporous titanium dioxide nanotubes

Pringle

Corr

et al. 2017

“…We have also shown that argon plasma generated inside water produces hydrogen peroxide, while air plasma in water produced nitrate ions . Separate studies have shown that the nitrate ions present in the anodizing electrolyte can independently produce a porous structure on the Ti, which finally led to the nanotubular structure . Another study has shown that hydrogen peroxide mixed with other chemicals in the anodizing electrolyte mixture serves as a good oxidizing agent – it supplies oxygen and enables more oxidation of titanium during anodization to form nanotubes …”

Section: Introductionmentioning

confidence: 81%

An environmentally friendly in situ plasma and anodization method to produce titanium dioxide nanotubes

Pringle

Chen

et al. 2017

An environmental friendly route to synthesize titanium dioxide nanotube powder is developed using a semi‐batch reactor set‐up that combines both anodization and the plasma treatment of water. A constant supply of the reactive plasma species, such as nitrate and hydrogen peroxide, in the semi‐batch reactor facilitates the formation of titanium dioxide nanotubes during the anodization of titanium. The results are compared against a conventional batch reactor set‐up that uses the same plasma‐treated water constantly during the anodization, which impacts the quality of the nanotubes produced. The semi‐batch reactor set‐up resulted in the formation of powders of titanium dioxide nanotubes with better physical and chemical qualities than those produced in the batch set‐up.

“…In a recent study conducted using an aqueous electrolyte containing nitric acid and ethylene glycol to anodize Ti, it was identified that different forms of TiO 2 such as nanoporous films, nanotubes, nanofibers, or fragile nanorods with an interstitially doped nitrogen were produced upon use of different concentrations of nitric acid in the electrolyte . Thus it was concluded that the nitrate ions (NO 3 − ) form a thermodynamically unstable, water soluble anionic complex of [TiO 2 − x (NO 3 ) x ] m − n ( m > n , 0 < x < 2), leading to the formation of a porous structure. This anionic complex further decomposes during the anodization and produces stable TiO 2 .…”

Section: Introductionmentioning

confidence: 99%

Plasma treated water – A promising electrolyte to produce nanoporous titanium dioxide nanotubes

Sadek

Magniez

et al. 2017

Plasma‐treated water is used as an environmentally friendly electrolyte for the synthesis of nanoporous titanium dioxide nanotubes by anodization of titanium. The possible mechanism of nanotube formation in the process is studied. The reactive species hydrogen peroxide and nitrate can be selectively produced in a gas bubble discharge in liquid using argon plasma or air plasma, respectively. It is observed that hydrogen peroxide enhances only the formation of an oxide layer, while nitrate forms pores on this oxide layer. It is proposed that the nitrate determines the formation of nanoporous nanotubes, while hydrogen peroxide enhances the oxidation.