Advanced Nanocrystal-Dispersed Coatings from Metal Oxide Gels with Hot-Water Treatment under External Fields

外部场下热水处理的金​​属氧化物凝胶先进纳米晶体分散涂层

• 批准号: 16360327
• 负责人: MATSUDA Atsunori
• 金额: $ 9.6万
• 依托单位: Toyohashi University of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16360327/
• 关键词: Sol-Gel Method; External Field; Hot-Water Treatment; Nanocrystal; Coating; Titania; Zinc Oxide; Morphology Control

External fields of vibrations and electric voltages affected the nanostructure of titania crystallites formed on SiO_2-TiO_2 gel coatings during hot-water treatment. Without the external fields granular anatase nanocrystals of 30-50 nm in size were formed on the coatings during the hot-water treatment, whereas the shape of the precipitates became sheetlike by applying a vibration to the substrate during hot-water treatment. Similar changes in shape of the precipitates on the coatings were also observed, and ramiform (branchlike) crystallites were 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(TiO_2)・nH_2O, 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 fo … More r the preparation of the coatings can be lowered at about 60℃ under atmospheric pressure, so that the coatings have a great potential for applications to various substrates including organic polymers with poor heat resistance.The addition of supramolecular assemblies of CTAB, P123, and F127 in the SiO_2-TiO_2 gel films permits the formation porous film structure and highly dispersion of anatase nanocrystals in the whole films after hot-water treatment. When the anatase nanocrystal-dispersed, porous films were irradiated with UV light, residual surfactants were completely eliminated due to the photocatalytic effects of the nanocrystals.SiO_2-TiO_2 spherical microparticles of about 0.7 μm in diameter have been prepared by the sol-gel method. Anatase nanocrystals were formed in the microparticles and their specific surface area was increased after a hot-water treatment at 90℃. Particulate, thick films were electrophoretically deposited on indium-tin oxide (ITO)-coated glass substrates using the anatase nanocrystal-precipitated SiO_2-TiO_2 microparticles.Hot water treatments were also found to be effective to form nanostructure as well as nanocrystals for Al_2O_3, SnO_2 and ZnO gel films at low temperatures. Cubic SnO_2 and hexagonal ZnO crystallites were precipitated by the hot water treatment, whereas AlO(OH) crystallite were formed on the Al_2O_3 film. With respect to ZnO gel coatings, the electric voltage and type of substrates showed a significant influence on the crystal habit of ZnO on the negative electrode. Hexagonal columnar and petal-like crystallites, which were oriented in the C-axis direction, were formed ITO-coated glass substrate and Si wafer, respectively. Less

外部振动场和电压影响了热水处理过程中sio2 - tio_2凝胶涂层上形成的二氧化钛微晶的纳米结构。在没有外场的情况下，在热水处理过程中涂层上形成了30-50 nm大小的粒状锐钛矿纳米晶体，而在热水处理过程中对基体施加振动时，析出物的形状变成了片状。涂层上析出物的形状也发生了类似的变化，在衬底之间施加电场，在负极处形成了枝状晶体。片状和枝状晶体主要由水合二氧化钛m（TiO_2）·nH_2O组成，呈鳞状晶状，d-间距为0.6 ~ 0.8 nm。二氧化钛纳米片具有较大的表面体积比，具有优异的润湿性和防雾性。在常压下，涂层的制备温度可降低到60℃左右，因此涂层在耐热性较差的有机聚合物等各种基材上具有很大的应用潜力。通过在SiO_2-TiO_2凝胶膜中加入CTAB、P123和F127的超分子组装体，使得热水处理后的SiO_2-TiO_2凝胶膜形成多孔膜结构，锐钛矿纳米晶体在整个膜中高度分散。当锐钛矿纳米晶体分散后，用紫外光照射多孔膜，由于纳米晶体的光催化作用，残留的表面活性剂被完全消除。采用溶胶-凝胶法制备了直径约0.7 μm的SiO_2-TiO_2球形微粒子。经90℃热水处理后，颗粒中形成锐钛矿纳米晶，其比表面积增大。采用锐钛矿纳米晶沉淀SiO_2-TiO_2微粒，电泳在氧化铟锡（ITO）镀膜玻璃基底上沉积颗粒状厚膜。在低温条件下，热水处理对Al_2O_3、SnO_2和ZnO凝胶膜的纳米结构和纳米晶体的形成也很有效。通过热水处理，在Al_2O_3薄膜上形成了立方SnO_2和六方ZnO晶体，而在Al_2O_3薄膜上形成了AlO（OH）晶体。对于ZnO凝胶涂层，电压和衬底类型对ZnO在负极上的结晶习性有显著影响。在涂覆ito的玻璃基片和硅片上分别形成了沿c轴取向的六角形柱状晶和花瓣状晶。少

项目成果

Characterization of Anatase Nanocrystals-Precipitated Coatings from (100-x)SiO_2 xTiO_2 Get Films via the Sol-Gel Process with Boiling Hot Water Treatment

(100-x)SiO_2 xTiO_2 通过溶胶-凝胶法和沸腾热水处理获得薄膜的锐钛矿纳米晶体沉淀涂层的表征

• 发表时间: 2005
• 期刊: Journal of Materials Research 20[1]
• 作者: 松田厚範;辰巳砂昌弘;松田厚範;A.Matsuda et al.
• 通讯作者: A.Matsuda et al.

「有機・無機ナノ複合材料の新局面」B編 ゾル-ゲル法による有機・無機ナノハイブリッドの創製

“有机-无机纳米复合材料的新方面”B部分：溶胶-凝胶法制备有机-无机纳米杂化物

• 发表时间: 2004
• 作者: A.Matsuda;M.Tatsumisago (分担);松田厚範 (分担);松田厚範(分担)
• 通讯作者: 松田厚範(分担)

External-Field Hot-Water Treatments of Sol-Gel Derived SiO2-TiO2 Coatings for Surface Nanostructure Control —A Review—

• DOI: 10.2109/jcersj.114.26
• 发表时间: 2006
• 期刊: Journal of the Ceramic Society of Japan
• 影响因子: 1.1
• 作者: A. Matsuda;M. Sakai;T. Kogure;K. Tadanaga;M. Tatsumisago

Characterization of Ramiform Precipitates Formed on SiO_2-TiO_2 Gel Coatings by Electric Field Hot Water Treatment

电场热水处理SiO_2-TiO_2凝胶涂层上枝状沉淀的表征

• 期刊: Journal of Non-Crystalline Solids (submitted)
• 作者: A.Matsuda;K.Kobayashi;T.Kogure;M.Sakai;K.Tadanaga;T.Minami;M.Tatsumisago
• 通讯作者: M.Tatsumisago

Titania Nanocrystals-Despersed Coatings fromSiO_2-TiO_2 Gel Films through Hydrolysis and Dissolution

SiO_2-TiO_2凝胶膜水解溶解二氧化钛纳米晶分散涂层

• 期刊: Key Engineering Materials 印刷中
• 作者: A.Matsuda;Y.Higashi;K.Tadanga;M.Tatsunisago;A.Matsuda et al.;A.Matsuda et al.
• 通讯作者: A.Matsuda et al.