Photoacoustic Spectra of Mixed TiO2 Ultrafine Powders with Rutile and Anatase Structures
Photoacoustic Spectra of Mixed TiO2 Ultrafine Powders with Rutile and Anatase Structures
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金红石和锐钛矿结构混合 TiO2 超细粉末的光声光谱
DOI：
10.1143/jjap.40.3587
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发表时间：
2001
影响因子：
1.5
通讯作者：
M. Ohmori
中科院分区：
文献类型：
--
作者：
T. Toyoda;Rie Taira;Q. Shen;M. Ohmori
我们通过光声（PA）光谱测量了具有金红石和钛酸盐结构的混合TiO 2超细粉末的光吸收，这是一种用于检测少量强散射材料的强大技术。用半导体带间跃迁理论测定了不同金红石含量的TiO_2超细粉体的带隙能E_g值。由PA强度谱和PA相谱得到的金红石型和金红石型TiO 2超细粉体的Eg值分别为3.00 eV和3.20 eV，表明PA谱的有效性。采用热氧化法制备了具有金红石和金红石结构的TiO 2混合超细粉体（粒径为20-140 nm）。金红石结构含量取决于热氧化温度。具有金红石和金红石结构的TiO 2混合超细粉体的Eg值随金红石含量的增加而不断减小。这表明表观Eg可以通过混合具有金红石和金红石结构的纳米TiO 2粉末来控制，因此，我们可以控制并获得具有介于金红石和金红石结构之间的任意表观Eg的TiO 2材料。
We have measured the optical absorption of mixed TiO2 ultrafine powders with rutile and tanatase structures by photoacoustic (PA) spectroscopy, which is a powerful technique for detecting small amounts of strongly scattered materials. The values of band-gap energies, Eg, of the TiO2 ultrafine powders with different rutile contents were determined by the theory of interband transition in semiconductors. The values of Eg of rutile and anatase structures of TiO2 ultrafine powders are 3.00 eV and 3.20 eV, respectively, obtained from PA intensity and PA phase spectra, indicating the usefulness of PA spectroscopy. Mixed TiO2 ultrafine powders with rutile and anatase structures (20–140 nm diameters) were obtained by thermal oxidation of TiCl4. Rutile structure contents depend on the thermal oxidation temperature. The value of Eg of a mixed TiO2 ultrafine powder with rutile and anatase structures decreases continuously with the increase of the rutile content. This indicates that the apparent Eg can be controlled by mixing the nanometer-sized TiO2 powders with rutile and anatase structures, hence, we can control and obtain TiO2 materials with an arbitrary apparent Eg between rutile and anatase structures.