Electronic Materials Research Laboratory, School of Electronic and Information Engineering and International Center for Dielectric Research, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, People's Republic of China.
ACS Appl Mater Interfaces. 2011 Jul;3(7):2800-4. doi: 10.1021/am200685s. Epub 2011 Jun 29.
Anodic growth of TiO(2) nanotubes has attracted intensive interests recently. However, the as-prepared TiO(2) nanotubes are usually amorphous and they generally need to be crystallized by sintering above 450 °C. Here, we report on a facile method to crystallize amorphous anodized TiO(2) nanotubes at a low temperature. We find that, simply by immersing them into hot water, the anodized TiO(2) nanotubes can be transformed from amorphous to crystalline state at a temperature as low as 92 °C. Results indicate that the hot water treatment might be a versatile strategy to crystallize amorphous anodized TiO(2) nanotubes at low temperature. Field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, UV-vis spectroscopy, and Brunauer-Emmett-Teller (BET) analysis via N(2) adsorption are used to characterize the resulting samples. In addition, the TiO(2) nanotubes in powder form are taken as photocatalysts to explore their potential applications. Results indicate that the sample after 35 h of hot water treatment shows the highest photoactivity, which is as efficient as the commercial photocatalyst Degussa P25. The photocatalytic testing results demonstrate that the hot water treatment reported in this study can be an alternative approach to the conventional methods.
阳极生长的 TiO(2) 纳米管最近引起了广泛的关注。然而，所制备的 TiO(2) 纳米管通常是无定形的，它们通常需要在 450°C 以上的温度下烧结来结晶。在这里，我们报告了一种在低温下将无定形阳极氧化 TiO(2) 纳米管结晶的简便方法。我们发现，只需将它们浸入热水中，在低至 92°C 的温度下，阳极氧化的 TiO(2) 纳米管就可以从无定形转变为晶态。结果表明，热水处理可能是在低温下结晶无定形阳极氧化 TiO(2) 纳米管的一种通用策略。通过场发射扫描电子显微镜、透射电子显微镜、X 射线衍射分析、紫外-可见分光光度计和 Brunauer-Emmett-Teller (BET) 通过 N(2) 吸附对所得样品进行分析。此外，还将粉末状的 TiO(2) 纳米管用作光催化剂来探索其潜在应用。结果表明，经过 35 小时热水处理的样品表现出最高的光活性，其效率与商业光催化剂 Degussa P25 相当。光催化测试结果表明，本研究中报道的热水处理可以作为传统方法的替代方法。
