Influence of the growth morphology of single-walled carbon nanotubes on gas sensing performance
Influence of the growth morphology of single-walled carbon nanotubes on gas sensing performance
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DOI：
10.1088/0957-4484/17/17/023
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发表时间：
2006-09
期刊：
影响因子：
3.5
通讯作者：
W. Wongwiriyapan;S. Honda;H. Konishi;T. Mizuta;T. Ohmori;Y. Kishimoto;T. Ito;T. Maekawa;K. Suzuki;H. Ishikawa;T. Murakami;K. Kisoda;H. Harima;K. Oura;M. Katayama
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文献类型：
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作者：
W. Wongwiriyapan;S. Honda;H. Konishi;T. Mizuta;T. Ohmori;Y. Kishimoto;T. Ito;T. Maekawa;K. Suzuki;H. Ishikawa;T. Murakami;K. Kisoda;H. Harima;K. Oura;M. Katayama
我们研究了单壁碳纳米管（SWNT）的生长形态对气体传感性能的影响。采用热化学气相沉积法在氧化铝基底上直接合成了单壁碳纳米管薄膜。通过改变生长温度，获得了密度、直径分布和取向方面不同形态的单壁碳纳米管。垂直排列的高密度单壁碳纳米管在 750 °C 下生长，而水平放置的低密度单壁碳纳米管网络在 800-950 °C 的温度范围内生长。所得单壁碳纳米管对 NO2 的传感器响应在室温下进行了表征。研究发现，单壁碳纳米管的密度在很大程度上决定了传感器的性能；密度最低的单壁碳纳米管网络表现出最高的传感器灵敏度。使用不同厚度的铁/铝多层催化剂合成的密度控制的单壁碳纳米管的表征证明了这一点。低密度SWNT网络的高传感器灵敏度可能归因于抑制SWNT束的形成和窄带隙传导路径的减少，从而提高了气体分子在SWNT上的吸附概率和化学门控效率。
We investigated the impact of the growth morphology of single-walled carbon nanotubes (SWNTs) on gas sensing performance. An SWNT film was directly synthesized on alumina substrate by thermal chemical vapour deposition. Different morphologies of the SWNTs in terms of density, diameter distribution and orientation were obtained by varying the growth temperature. Vertically aligned SWNTs with a high density were grown at 750 °C, while horizontally lying SWNT networks with a low density were grown in the temperature range 800–950 °C. The sensor response of the resultant SWNTs to NO2 was characterized at room temperature. It was found that the density of SWNTs strongly dominates sensor performance; the SWNT networks with the lowest density exhibited the highest sensor sensitivity. This was evidenced by characterization of density-controlled SWNTs synthesized using different thicknesses of an Fe/Al multilayer catalyst. The high sensor sensitivity for low-density SWNT networks is likely to be attributed to suppression of the formation of SWNT bundles and reduction of narrow-band-gap conduction paths, resulting in the enhancement of the adsorption probability and chemical gating efficiency of gas molecules on SWNTs.