Crystal Structures of Titanate Nanotubes: A Raman Scattering Study
Crystal Structures of Titanate Nanotubes: A Raman Scattering Study
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DOI：
10.1021/ic801508k
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发表时间：
2009-02-16
影响因子：
4.6
通讯作者：
Norby, Poul
中科院分区：
文献类型：
--
作者：
Gao, Tao;Fjellvag, Helmer;Norby, Poul
从振动光谱的角度讨论了用氢氧化钠处理后酸洗制备的钛酸盐纳米管的晶体结构。通过分析晶态二氧化钛(锐钛矿型和金红石型)和层状质子型钛酸盐的拉曼散射数据，建立了TiO6八面体的振动特征与聚合性之间的关系。然后，通过与晶态二氧化钛和层状质子钛酸盐的拉曼散射光谱的比较，确定了钛酸盐纳米管中TiO6八面体的聚合性质。结果表明，钛酸盐纳米管由二维八面体TiO6层组成，具有类钙钛矿(γ-FeOOH)型层状结构。这一结论通过考虑由原始涡卷状钛酸盐纳米管衍生的TiO6八面体层组装而成的重新堆积的钛酸酯的拉曼散射性质进一步得到证实。我们的研究结果为验证不同实验条件下的二氧化钛碱处理产物的晶体结构提供了一种方便的方法。
Crystal structures of titanate nanotubes prepared from a NaOH treatment of TiO2 with subsequent acid washing were discussed from a viewpoint of vibrational spectroscopy. The correlation between the vibrational feature and the polymerization nature of the TiO6 octahedron was established by analyzing Raman scattering data of crystalline TiO2 (anatase and rutile) and layered protonic titanates. Then, the polymerization nature of TiO6 octahedra in the titanate nanotubes was identified by comparing their Raman scattering spectra with those of the crystalline TiO2 and layered protonic titanates. It demonstrated that the titanate nanotubes consist of two-dimensional TiO6 octahedral host layers with a lepidocrocite (gamma-FeOOH)-type layered structure. This conclusion was confirmed further by considering the Raman scattering properties of a restacked titanate prepared by assembling TiO6 octahedral layers derived from the original scroll-like titanate nanotubes. Our findings offered a convenient approach to validate the crystal structures of the products from an alkaline treatment of TiO2 under different experimental conditions.