CSIRO, Earth Science and Resource Engineering, Wealth from Oceans Flagship, Kensington, WA, Australia.
Talanta. 2011 Sep 15;85(3):1648-57. doi: 10.1016/j.talanta.2011.06.062. Epub 2011 Jun 30.
This report compares the performance of polymer and carbon nanotube-polymer composite membranes on a quartz crystal microbalance (QCM) sensor for the detection of aromatic hydrocarbons (benzene, toluene, ethylbenzene, p-xylene and naphthalene) in aqueous solutions. Several different polymers (polystyrene, polystyrene-co-butadiene, polyisobutylene and polybutadiene) and types of functionalized carbon nanotubes (multi-walled and single-walled carbon nanotubes) were investigated at varying carbon nanotube (CNT) loading levels and film thicknesses. In a majority of instances, the difference in response between membranes comprising pure polymer and membranes containing 10% (w/w) carbon nanotubes were not statistically significant. However, a notable exception is the decreasing sensitivity towards p-xylene with increasing carbon nanotube content in a polybutadiene film. This variation in sensitivity can be attributed to a change in the sorption mechanism from absorption into the polymer phase to adsorption onto the carbon nanotube sidewalls. With much thicker coatings of 10% (w/w) carbon nanotube in polybutadiene, the sensitivity towards toluene was higher compared to the pure polymer. The increased toluene sensitivity may be partially attributed to an increase in the sorption capacity of a carbon nanotube polymer composite film relative to its corresponding pure polymer film. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) measurements were performed to understand the mechanism of sorption and these studies showed that the addition of functionalized CNT to the polymer increases the absorption of certain types of hydrocarbons. This study demonstrates that carbon nanotubes can be incorporated into a polymer-coated QCM sensor and that composite films may be used to modify the QCM response and selectivity during the analysis of complex hydrocarbon mixtures.
本报告比较了聚合物和碳纳米管-聚合物复合膜在石英晶体微天平（QCM）传感器上对水溶液中芳烃（苯、甲苯、乙苯、对二甲苯和萘）的检测性能。研究了几种不同的聚合物（聚苯乙烯、聚苯乙烯-丁二烯共聚物、聚异丁烯和聚丁二烯）和不同类型的功能化碳纳米管（多壁和单壁碳纳米管），并在不同的碳纳米管（CNT）负载水平和膜厚度下进行了研究。在大多数情况下，由纯聚合物组成的膜和含有 10%（重量比）碳纳米管的膜之间的响应差异在统计学上并不显著。然而，一个值得注意的例外是，在聚丁二烯膜中，随着碳纳米管含量的增加，对二甲苯的灵敏度呈下降趋势。这种灵敏度的变化可归因于吸附机制从聚合物相中吸收到碳纳米管侧壁吸附的变化。在聚丁二烯中具有更厚的 10%（重量比）碳纳米管涂层时，对甲苯的灵敏度比纯聚合物高。对甲苯的灵敏度增加可能部分归因于碳纳米管聚合物复合膜相对于其相应的纯聚合物膜的吸附容量增加。进行了衰减全反射傅里叶变换红外光谱（ATR-FTIR）测量，以了解吸附机制，这些研究表明，向聚合物中添加功能化 CNT 会增加某些类型碳氢化合物的吸收。本研究表明，碳纳米管可以被掺入聚合物涂覆的 QCM 传感器中，并且复合膜可用于在分析复杂烃混合物期间修改 QCM 响应和选择性。
