TiO2 Nanotubes - Annealing Effects on Detailed Morphology and Structure
TiO2 Nanotubes - Annealing Effects on Detailed Morphology and Structure
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DOI：
10.1002/ejic.201000608
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发表时间：
2010-09-01
影响因子：
2.3
通讯作者：
Schmuki, Patrik
中科院分区：
文献类型：
--
作者：
Albu, Sergiu P.;Tsuchiya, Hiroaki;Schmuki, Patrik
本工作涉及自组织二氧化钛纳米管层形成在钛金属基板上的阳极氧化。对于几乎任何电气或光电应用，这些原本无定形的纳米管层需要转化为纳米管。最常见的是，这是通过在大约450摄氏度的温度下退火来完成的。在目前的工作中，我们使用TEM和XRD来比较在350摄氏度的明显较低的温度下的退火与在既定的450摄氏度的退火。HRTEM结果表明，两种退火处理导致纳米管壁中的晶粒尺寸相当;然而，在450 ℃下，在纳米管壁中产生许多缺陷（纳米级裂纹）。此外，在450摄氏度下的处理导致在管层下面形成（金红石）氧化物层。这些因素会显著影响管的整体性能。此外，我们指出了一些影响，应仔细考虑使用高分辨电子显微镜研究时，如电子束诱导的结晶或管直径收缩的二氧化钛纳米管。
The present work deals with self-organized TiO2 nanotube layers formed on a Ti metal substrate by anodization. For virtually any electrical or photoelectric application, these originally amorphous nanotube layers need to be converted to anatase. Most frequently, this is done by annealing at temperatures of approximately 450 degrees C. In the present work we use TEM and XRD to compare the annealing at a significantly lower temperature of 350 degrees C with that at the established 450 degrees C. HRTEM results show that both annealing treatments lead to comparable grain sizes in the nanotube walls; however, at 450 degrees C numerous defects (nanoscopic cracks) are created in the nanotube walls. Moreover, the treatment at 450 degrees C leads to the formation of a (rutile) oxide layer underneath the tube layers. These factors can considerably affect the overall properties of the tubes. Additionally, we point out some effects that should be carefully considered when using HRTEM investigation on TiO2 nanotubes such as e-beam-induced crystallization or tube diameter shrinkage.