Microstructure control of TiO2 nanotubular films for improved VOC sensing
Microstructure control of TiO2 nanotubular films for improved VOC sensing
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DOI：
10.1016/j.snb.2010.01.069
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发表时间：
2011-06
影响因子：
8.4
通讯作者：
M. Seo;M. Yuasa;T. Kida;J. Huh;N. Yamazoe;K. Shimanoe
中科院分区：
文献类型：
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作者：
M. Seo;M. Yuasa;T. Kida;J. Huh;N. Yamazoe;K. Shimanoe
制备了由 TiO2 纳米管组成的多孔气体传感薄膜，用于检测挥发性有机化合物 (VOC)，例如酒精和甲苯。为了控制TiO2纳米管薄膜的微观结构，采用球磨处理来缩短TiO2纳米管的长度，提高薄膜的颗粒堆积密度，同时不破坏其管状形貌和晶体结构。扫描电子显微镜 (SEM) 和汞孔隙率测定法证实，球磨处理通过诱导纳米管之间更紧密的接触，成功地改变了气敏膜的孔隙率。使用纳米管的传感器在球磨处理 3 小时后，在 500°C 的工作温度下表现出改善的传感器响应和对甲苯 (50ppm) 的选择性。然而，广泛的球磨处理并没有增强原始传感器响应，这可能是由于薄膜孔隙率的降低。获得的结果表明，在颗粒堆积密度和孔隙率方面控制传感层的微观结构对于检测大尺寸有机气体分子非常重要。
Porous gas sensing films composed of TiO2nanotubes were fabricated for the detection of volatile organic compounds (VOCs), such as alcohol and toluene. In order to control the microstructure of TiO2nanotubular films, ball-milling treatments were used to shorten the length of TiO2nanotubes and to improve the particle packing density of the films without destroying their tubular morphology and crystal structure. The ball-milling treatment successfully modified the porosity of the gas sensing films by inducing more intimate contacts between nanotubes, as confirmed by scanning electron microscopy (SEM) and mercury porosimetry. The sensor using nanotubes after the ball-milling treatment for 3h exhibited an improved sensor response and selectivity to toluene (50ppm) at the operating temperature of 500°C. However, an extensive ball-milling treatment did not enhance the original sensor response, probably owing to a decrease in the porosity of the film. The results obtained indicated the importance of the microstructure control of sensing layers in terms of particle packing density and porosity for detecting large sized organic gas molecules.