Photocatalysts with Tunnel Structures for Decomposition of Orgnic Compounds

用于分解有机化合物的隧道结构光催化剂

• 批准号: 07555249
• 负责人: INOUE Yasunobu
• 金额: $ 3.9万
• 依托单位: Nagaoka 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: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07555249/
• 关键词: photocatalysts; tunnel structures; titanates; toluene; water decomposition; ruthenium oxide; sol-gel; 酸化ルテニウム; ゾルゲル法; トンネル構造酸化物; 微量有機物酸化

In sn attempt to develop a photocatalyst which has high dfficiency for the decomposition of toluene and water, alkaline metal bexa-titanates, M_2Ti_6O_<13> (M=Na, K,Rb) with a rectangular tunnel structute barium tetra-titanate, BaTi_4O_9, with a pentagonal-prism tunnel structure were combined with transition metals (Mn, Pt, Cu, Co, Fe, Ru, Ir, Ta) and their oxides. The decomposition of toluene on these photocatalysys wsa examined for gaseous mixtures of air-toluene and air-toluene-water. The highest photocatalytic activity wsa obtained for a RuO_2/BaTi_4O_9system in the presence of water, thus indicating that the decomposition of water is an important step in the reaction. A sol-gel method was employed to the preparation of fine BaTi_4O_9 particles. Upon heat treatment, the crystallization of the prepared gels occurred at around 873 K.Well-crystallized BaTi_4O_9 showed a single Raman peak at 860cm^<-1>, characteristic of a double bond-like short Ti-O bond and resulted in the enhancement of the photocatalytic activity for water decomposition. ESR spectra showed that active BaTi_4O_9 produced a signal with g=2.018 and g=2.004 at 77 K under UV irradiation in the presence of oxygen. This signal was assigned to a surface lattice O-radical which is proposed to be responsible for the photocatalysis as a hole trap center. The tunnel structure titanates are concluded to be useful for the development of photocatalysts with high efficiency for oxidation reactions.

为了开发高效降解甲苯和水的光催化剂，将具有矩形隧道结构的碱金属六钛酸盐M_2Ti_6O_<13>（M=Na，K，Rb）和具有五棱柱隧道结构的四钛酸钡BaTi_4O_9与过渡金属（Mn，Pt，Cu，Co，Fe，Ru，Ir，Ta）及其氧化物复合。以空气-甲苯和空气-甲苯-水混合气体为对象，考察了甲苯在这些光催化剂上的分解情况。RuO_2/BaTi_4O_9体系在有水存在时光催化活性最高，说明水的分解是反应的重要步骤。采用溶胶-凝胶法制备了BaTi_4O_9超细粒子。热处理后，所制备的凝胶在873 K左右开始结晶，结晶良好的BaTi_4O_9在860 cm ~ 2处出现一个拉曼峰<-1>，具有Ti-O短双键的特征，从而提高了光催化分解水的活性。ESR谱表明活性BaTi_4O_9在77 K时，在紫外光照射下，有氧存在时产生g=2.018和g=2.004的信号。这个信号被分配到一个表面晶格O-自由基，这是建议负责作为空穴陷阱中心的电子。隧道结构钛酸盐的结论是有用的开发与高效率的氧化反应的光催化剂。

项目成果

M.Kohno, S.Ogura, Y.Inoue: "Preparation of BaTi_4O_9 by a Sol-gel method and its photocatalytic activity for water decomposition" J.Mat.Chem.6. 1921-1924 (1996)

M.Kohno、S.Ogura、Y.Inoue：“溶胶-凝胶法制备 BaTi_4O_9 及其光催化水分解活性”J.Mat.Chem.6。

Mitsuru Kohno, Shuji Ogura, Kazunori Sato, Yasunobu Inoue: "Properties of photocatalysts with tunnel structures : formation of a surface lattice O-radical by the UV irradiation of BaTi4O9 with a pentagonal-prism tunnel structure." Chemical Physics Letters

Mitsuru Kohno、Shuji Ogura、Kazunori Sato、Yasunobu Inoue：“具有隧道结构的光催化剂的特性：通过具有五棱柱隧道结构的 BaTi4O9 的紫外线照射形成表面晶格 O 自由基。”

M.Kohno, T.Kaneko, S.Ogura, K.Sato, Y.Inoue: "Dispersion of ruthenium oxide on barium titanates (Ba_6Ti_<17>O_<40>,Ba_4Ti_<13>O_<30>,BaTi_4O_9,Ba_2Ti_4O_<20>) and photocatalytic activity" J.Chem.Soc.,Faraday Trans.94(1). 89-94 (1998)

M.Kohno、T.Kaneko、S.Ogura、K.Sato、Y.Inoue：“氧化钌在钛酸钡上的分散体 (Ba_6Ti_<17>O_<40>,Ba_4Ti_<13>O_<30>,BaTi_4O_9,Ba_2Ti_4O_

"Effects of Tunnel Structures of BaTi_4O_9 and Na_2Ti_6O_<13> on Photocatalytic Activity and Photoexcited Charge Separation" Proc. 11th Intern. Congr. Catal.(印刷中).

“BaTi_4O_9 和 Na_2Ti_6O_<13> 的隧道结构对光催化活性和光激发电荷分离的影响”Proc. 11th Congr。

M.Kohno, S.Ogura, K.Sato, Y.Inoue: "Properties of photocatalysts with tunnel structures : formation of a surface lattice O radical by the UV irradiation of BaTi_4O_9" Chem.Phys.Lett.267. 72-76 (1997)

M.Kohno、S.Ogura、K.Sato、Y.Inoue：“具有隧道结构的光催化剂的特性：BaTi_4O_9 的紫外线照射形成表面晶格 O 自由基”Chem.Phys.Lett.267。