Exploring the chemical sensitivity of a carbon nanotube/green tea composite.
Single-walled carbon nanotubes (SWNTs) possess unique electronic and physical properties, which make them very attractive for a wide range of applications. In particular, SWNTs and their composites have shown a great potential for chemical and biological sensing. Green tea, or more specifically its main antioxidant component, epigallocatechin gallate (EGCG), has been found to disperse SWNTs in water. However, the chemical sensitivity of this SWNT/green tea (SWNT/EGCG) composite remained unexplored. With EGCG present, this SWNT composite should have strong antioxidant properties and thus respond to reactive oxygen species (ROS). Here we report on fabrication and characterization of SWNT/EGCG thin films and the measurement of their relative conductance as a function of H(2)O(2) concentrations. We further investigated the sensing mechanism by Fourier transform infrared (FTIR) spectroscopy and field-effect transistor measurements (FET). We propose here that the response to H(2)O(2) arises from the oxidation of EGCG in the composite. These findings suggest that SWNT/green tea composite has a great potential for developing simple resistivity-based sensors.
Department of Chemistry, University of Pittsburgh and the National Energy Technology Laboratory, Pittsburgh, Pennsylvania 15260, United States.
Yanan
Y
Chen
Yang Doo
YD
Lee
Harindra
H
Vedala
Brett L
BL
Allen
Alexander
A
Star
D002392:Catechin / Q000031:analogs & derivatives* / Q000737:chemistry; D004566:Electrodes; D006861:Hydrogen Peroxide / Q000737:chemistry; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D013057:Spectrum Analysis; D013662:Tea / Q000737:chemistry*; D014173:Transistors, Electronic
D037742:Nanotubes, Carbon; D013662:Tea; D002392:Catechin; D006861:Hydrogen Peroxide; C045651:epigallocatechin gallate