Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Engineering / Faculty of Engineering >
Peer-reviewed Journal Articles, etc >
External-Field Hot-Water Treatments of Sol-Gel Derived SiO2-TiO2 Coatings for Surface Nanostructure Control : A Review
This item is licensed under:Creative Commons Attribution-NoDerivatives 4.0 International
Title: | External-Field Hot-Water Treatments of Sol-Gel Derived SiO2-TiO2 Coatings for Surface Nanostructure Control : A Review |
Other Titles: | 外部場温水処理によるゲルーゾルSiO2-TiO2系コーティング膜の表面ナノ構造制御 : 総説 |
Authors: | MATSUDA, Atsunori1 Browse this author | SAKAI, Mototsugu2 Browse this author | KOGURE, Toshihiro3 Browse this author | TADANAGA, Kiyoharu4 Browse this author →KAKEN DB | TATSUMISAGO, Masahiro5 Browse this author |
Authors(alt): | 松田, 厚範1 | 逆井, 基次2 | 小暮, 敏博3 | 忠永, 清治4 | 辰巳砂, 昌弘5 |
Keywords: | External field | Sol-gel coating | Hot-water treatment | Titania | Nanosheet | Nanocrystal |
Issue Date: | Jan-2006 |
Publisher: | Ceramic Society of Japan |
Journal Title: | Journal of the Ceramic Society of Japan |
Journal Title(alt): | 日本セラミックス協会学術論文誌 |
Volume: | 114 |
Issue: | 1325 |
Start Page: | 26 |
End Page: | 35 |
Publisher DOI: | 10.2109/jcersj.114.26 |
Abstract: | This review paper is focused on the area of titania nanocoatings prepared from sol-gel derived films by hot-water treatment under external reaction fields to design their functionality through the control of their surface morphology and crystallinity at low processing temperatures. First, the formation of titania nanocrystalline coatings at low temperatures by wet chemical procedures is briefly reviewed. Second, a concept of material design based on an external-field hot-water treatment for sol-gel derived films and the effects of the external fields on the formation of titania nanocrystals from the sol-gel derived films are discussed. Finally, promising characteristics of the resultant titania nanocrystal-dispersed coatings with unique morphology are described. External fileds of vibrations and electric voltages affect the nanostructure of titania crystallites formed on SiO2-TiO2 gel coatings during hot-water treatment. Without the external fields granular anatase nanocrystals of 30-50 nm in size are formed on the coatings during the hot-water treatment, whereas the shape of the precipitates becomes sheetlike by applying a vibration to the substrate during hot-water treatment. Similar changes in shape of the precipitates on the coatings are also observed, and ramiform (branchlike) crystallites are formed at the negative electrode by applying an electric field between the substrates. The sheetlike and ramiform crystallites are mainly composed of a hydrated titania, m(TiO2)•nH2O, with the lepidocrocite-like layered structure with a d-spacing of 0.6-0.8 nm. Titania nanosheets are characterized by a large surface-to-volume ratio, which gives rise to the excellent wettability for water and antifogging properties. Processing temperatures for the preparation of the coatings are lower than 100°C under atmospheric pressure, so that the coatings have a great potential for applications to various substrates including organic polymers with poor heat resistance. |
Rights: | https://creativecommons.org/licenses/by-nd/4.0/deed.ja |
Type: | article |
URI: | http://hdl.handle.net/2115/73945 |
Appears in Collections: | 工学院・工学研究院 (Graduate School of Engineering / Faculty of Engineering) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 忠永 清治
|