Abstract

In this study, an inexpensive simple method for the fabrication of efficient hydrogen (H₂) gas sensor based on carbon nanotubes (CNTs) was presented. The CNTs were synthesized using microwave oven and deposited onto SiO₂ substrate by a dielectrophoretic method. The as-grown CNTs showed an n-type behavior because CNTs possess the characters of both metallic and semiconductor when placed between the two electrodes, meanwhile, the current was directed mostly by metallic tubes. Upon exposure to H₂ gas at room temperature, the CNTs exhibited high sensitivity up to 315% at 140 ppm H₂, and relatively good sensitivity of 40% at a very low H₂ gas concentration of 20 ppm. To the best of our knowledge, this is the first work involving the fabrication of CNTs for detecting a low H₂ gas concentration of 20 ppm at RT with high sensitivity comparing with other previous studies.

摘要

在这项研究中，提出了一种基于碳纳米管 (CNT)的高效氢 (H ₂ ) 气体传感器的廉价简单制造方法。使用微波炉合成碳纳米管，并通过介电泳法沉积在 SiO ₂衬底上。生长的碳纳米管显示出 n 型行为，因为碳纳米管放置在两个电极之间时同时具有金属和半导体的特性，同时电流主要由金属管引导。在室温下暴露于 H ₂气体时，碳纳米管在 140 ppm H ₂下表现出高达 315% 的高灵敏度，在非常低的 H ₂下表现出相对良好的 40% 灵敏度气体浓度为 20 ppm。据我们所知，这是第一项涉及制造 CNT 的工作，与其他先前的研究相比，它在 RT 下以高灵敏度检测20 ppm的低 H ₂气体浓度。