Department of Biosystems Engineering, Zhejiang University, Hangzhou 310058, China.
Analyst. 2013 Sep 21;138(18):5265-73. doi: 10.1039/c3an36690a. Epub 2013 Jul 16.
A novel gas sensor based on composite films of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) and single-walled carbon nanotubes (SWCNTs) was fabricated for the detection of fishy trimethylamine (TMA) vapor. The SWCNTs were functionalized by O2 plasma treatment to improve their solubility in the polymeric matrix, and alternative current dielectrophoresis was utilized for the first time to assemble the PEDOT/PSS-SWCNTs composite film to enhance the response to TMA molecules. The high resolution transmission electron microscopy (HR-TEM) images showed that the SWCNTs maintained their bulk structure after O2 plasma functionalization. The scanning electron microscopy (SEM) images of the composite film showed that the oxidized SWCNTs were orderly arranged and uniformly dispersed into the polymer by dielectrophoresis. Compositional analyses of SWCNTs by X-ray photoelectron spectroscopy (XPS) suggested that O2 plasma functionalization could remove amorphous carbon from the nanotube surface and introduce more hydrophilic oxygen-containing groups, leading to the improvement of SWCNTs solubility in the polymeric matrix. Gas sensitivities of the composite films largely relied on the treatment conditions. Compared to the raw or acid-treated SWCNTs-doped composite films, the film doped with SWCNTs modified by O2 plasma at 30 W for 3 min exhibited the most sensitive and stable response characteristics to ppb-level TMA gas.
一种基于聚（3,4-亚乙基二氧噻吩）/聚（苯乙烯磺酸盐）（PEDOT/PSS）和单壁碳纳米管（SWCNTs）复合薄膜的新型气体传感器被制备用于检测鱼腥味三甲胺（TMA）蒸气。SWCNTs 通过 O2 等离子体处理进行功能化以提高其在聚合物基体中的溶解度，并且首次利用交流介电泳来组装 PEDOT/PSS-SWCNTs 复合薄膜以增强对 TMA 分子的响应。高分辨率透射电子显微镜（HR-TEM）图像表明，SWCNTs 在 O2 等离子体功能化后保持其本体结构。复合薄膜的扫描电子显微镜（SEM）图像显示，经介电泳处理后，氧化的 SWCNTs 被有序排列并均匀分散到聚合物中。X 射线光电子能谱（XPS）对 SWCNTs 的成分分析表明，O2 等离子体功能化可以从纳米管表面去除非晶态碳并引入更多亲水性含氧基团，从而提高 SWCNTs 在聚合物基体中的溶解度。复合薄膜的气体灵敏度在很大程度上依赖于处理条件。与原始或酸处理的 SWCNTs 掺杂复合薄膜相比，在 30 W 下处理 3 分钟的 O2 等离子体修饰的 SWCNTs 掺杂的薄膜对 ppb 级 TMA 气体表现出最敏感和稳定的响应特性。
