Development of Hyper Active Semiconductor Photocatalyst

高活性半导体光触媒的开发

• 批准号: 10555213
• 负责人: OHTANI Bunsho
• 金额: $ 5.89万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10555213/
• 关键词: Semiconductor Suspension; Photocatalysis; Ultrafast Laser; Titanium Dioxide; Anatase; Rutile; Electron-hole recombination; Recombination Rate Constant; 光触媒活性; ポンプ-プローブ法

This study aimed at rationalization of the hypothesis that the most decisive factors controlling the photocatalytic activity of semiconductor powders is surface area and crystallinity. The larger the surface area becomes, the more the reaction substrate molecules are adsorbed on the surface, to result in the higher activity, while the higher the crystallinity of particles, the smaller the crystal defect inducing electron-hole recombination. Therefore it is expected that semiconductor particles having large surface area and being high crystallinity should exhibit high photocatalytic activity. We have developed the novel method of titanium (IV) oxide preparation without the use of water ; (1) Hydrothermal Crystallization of Organic Media (HyCOM), (2) Thermal Decomposition (TD), and (3) Transfer Hydrolytic Crystallization in Alcohols (THyCA). The titanium (IV) oxide powders thus prepared had large surface area and high crystallinity of anatase crystallites. As expected from these physical properties, these powders showed the photocatalytic activity, under both aerated and deaerated conditions which is marked higher than that of highly active commercially available titanium (IV) oxide (Degussa P-25). Thus, we have confirmed the principle for the design of ultra-highly semiconductor photocatalyst and developed the novel synthetic methods. By using femtosecond laser systems, the reduced rate of electron-hole recombination was clarified.

本研究旨在合理化以下假设：控制半导体粉末光催化活性的最决定性因素是表面积和结晶度。表面积越大，表面吸附的反应底物分子越多，活性越高，而颗粒的结晶度越高，引起电子空穴复合的晶体缺陷越小。因此，期望具有大表面积和高结晶度的半导体颗粒应表现出高光催化活性。我们开发了不使用水制备氧化钛（IV）的新方法； (1) 有机介质水热结晶 (HyCOM)，(2) 热分解 (TD)，以及 (3) 醇中转移水解结晶 (THyCA)。由此制备的氧化钛(IV)粉末具有大的表面积和高锐钛矿微晶的结晶度。正如从这些物理特性所预期的那样，这些粉末在充气和脱气条件下都显示出光催化活性，其明显高于高活性的市售氧化钛 (IV) (Degussa P-25)。由此，我们确定了超高半导体光催化剂的设计原理并开发了新的合成方法。通过使用飞秒激光系统，电子空穴复合率的降低得到了澄清。

项目成果

H.Kominami, et al.: "Titanium(IV) Oxide Photocatalyst of Ultra-high Activity : a New Preparation Process Allowing Compatibility of High Adsorptivity and Low Electron-Hole Recombination Probability"Cat al.Lett. 56. 125-129 (1998)

H.Kominami等人：“超高活性钛(IV)氧化物光催化剂：一种兼具高吸附性和低电子空穴复合概率的新制备工艺”Cat al.Lett。

B.Ohtani: "Femtosecond Diffuse Reflectance Spectroscopy of Aqueous Titanium(IV) Oxide Suspension:Correlation of Electron-Hole Recombination Kinetics with Photocatalytic Activity" Chem.Lett.579-580 (1998)

B.Ohtani：“水性钛（IV）氧化物悬浮液的飞秒漫反射光谱：电子-空穴复合动力学与光催化活性的相关性”Chem.Lett.579-580（1998）

H.Kominami et al.: "Immobilization of Highly Active Titanium (IV) Oxide Particles.A Novel Strategy of Preparation of Transparent Photocatalytic Coatings"Appl.Cat al.B.Environ.. 30. 329-335 (2001)

H.Kominami 等人：“高活性钛 (IV) 氧化物颗粒的固定化。透明光催化涂层制备的新策略”Appl.Cat al.B.Environ.. 30. 329-335 (2001)

Ohtani, B., Kominami, H., Bowman, R.M., Colombo Jr., P., Noguchi, H.and Uosaki, K.: "Femtosecond Diffuse Reflectance Spectroscopy of Aqueous Titanium (IV) Oxide Suspension : Correlation of Electron-Hole Recombination Kinetics with Photocatalytic Activity"

Ohtani, B.、Kominami, H.、Bowman, R.M.、Colombo Jr., P.、Noguchi, H. 和 Uosaki, K.：“水相钛 (IV) 氧化物悬浮液的飞秒漫反射光谱：电子-空穴的相关性

Kominami, H., Kumamoto, H., Kera, Y.and Ohtani, B.: "Immobilization of Highly Active Titanium (IV) Oxide Particles. A Novel Strategy of Preparation of Transparent Photocatalytic Coatings"Appl. Catal. B.Environ.. 30. 329-335 (2001)

Kominami, H.、Kumamoto, H.、Kera, Y. 和 Ohtani, B.：“高活性钛 (IV) 氧化物颗粒的固定化。透明光催化涂层制备的新策略”