Sensing performance nanocomposites

Wu, C.-H., et al., Unique Pd/graphene nanocomposites constructed using supercritical fluid for superior electrochemical sensing performance. Journal of Materials Chemistry, 2012. 22(40) p. 21466-21471. 

Chemical Sensing Performance of Conjugated Polymer-Based Nanocomposites... 

Conducting polymers have been composited with any one of these materials constituting binary nanocomposites and any two of these materials constituting ternary nanocomposites with which the sensing performances of such advanced functional and hybrid materials have been improved by the synergistic effects especially for sensor applications. 

Analysis of diversity in response to polar and nonpolar vapors of all screened polymers was performed using PCA analysis followed by cluster analysis. The scores plots of the first three PCs (Fig. 5.12) illustrate the diversity of performance of all sensing polymers. The larger the distance between polymer data points, the larger the difference in the response pattern between the respective CdSe/polymer nanocomposites. To quantify this diversity, cluster analysis was further performed where the distances based on principal component scores were adjusted to unit variance.45 This distance measure, known as Mahalanobis distance, accounts for the different amount of variation in different directions. An example of such difference is shown in Fig. 5.12a, b, where the distance between polymer 4 and other polymers is much larger on the plot of PC 1 vs. PC 2 when compared with the plot of PC 2 vs. PC 3. 

The gas-sensing system consists of a Parr pressure chamber equipped with the necessary valves to achieve vacuum, introduce gases, and perform in situ four-probe conductivity measurements [68,69], Resistance values obtained for three types of different nanocomposite PANl-metal oxide films are shown in Figures 2.5 and 2.6. CO acts as an oxidant for PANl-metal oxide nanocomposite films and reveals a... 

The use of nanocomposites to reinforce traditional composites has also been increasing and will continue to be a near-term trend. The emphasis for these applications, however, has been on additional mechanical reinforcement rather than flammability reduction.Since more traditional fiber-filled composites are exposed to fire risk scenarios, it makes sense to use a nanocomposite with the traditional composite to improve both mechanical and flammability performance. Of course, this does create an additional level of complexity, especially in handling the large increases in viscosity seen with nanocomposites used with thermoset composites. At this time, most nanocomposite-fiberglass/carbon fiber composites are used for military and aerospace applications, but the benefit of lightweight materials may also move these materials into automotive and mass transportation (e.g., bus, rail), where flammability performance is strongly needed. 

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