Chitosan and Chitosan-co-Poly(ε-caprolactone) Grafted Multiwalled Carbon Nanotube Transducers for Vapor Sensing

Abstract

Vapor sensitive transducer films consisting of chitosan grafted (CNT-CS) and chitosan-co-polycaprolactone grafted (CNT-CS-PCL) multiwalled carbon nanotubes were prepared using a spray layer-by-layer technique. The synthesized materials (CNT-CS and CNT-CS-PCL) were characterized by Fourier transform infrared spectroscopy, 13C CP/MAS solid state nuclear magnetic resonance spectroscopy and thermogravimetric analysis. Both CNT-CS and CNT-CS-PCL transducers were analyzed for the response of volatile organic compounds and toluene vapors. The ranking of the relative resistance (A(r)) for both chitosan based transducers were as follows: toluene < chloroform < ethanol < methanol. The CNT transducer (CNT-CS) was correlated selectively with an exponential law to the inverse of Flory-Huggins interaction parameters, chi12. Dosing the films on the interdigitated electrodes with methanol, ethanol, chloroform and toluene vapors increased the film resistance of CNT-CS but decreased the resistance of CNT-CS-PCL compared to that of the reported transducers.

Graphite to Graphene via Graphene Oxide: An Overview on Synthesis, Properties, and Applications

“…The reduction of GO is carried in a stabilized medium; e.g., KOH-treated GO can be modified with hydroxyl, epoxy, or carboxylic acid groups. Covalent modification of graphene is done by using lithium reagents, isocynates, and di-isocynates to reduce hydrophilic character of GO, e.g., chitosan functionalized GO and CNT 33,54,55 for biological and medical applications. GO nanoplatelets also can be functionalized by polysodium styrene sulfonate, which is an example of noncovalent functionalization.…”

“…Graphane is also used in the application of biosensing due to its electrochemical oxidation. [26][27][28]30,32,33,45,55,59 Graphene materials are promising candidates for TCFs because of their high carrier mobility, electrical conductivity, and optical transmittance in the visible range of the spectrum. The optical transmittance (transparency) of chemically modified graphene is reported to be 83% at a wavelength of 1000 nm.…”

Polymer Based Hybrid Nanocomposites; A Progress Toward Enhancing Interfacial Interaction and Tailoring Advanced Applications

“…In addition, we also prepared CS/wheat gluten /GO ternary hybrid nanocomposites as well as CS based hybrid nanocomposites with silica, silsesquioxane, mesoporous silica, and carbon nanotube (CNT), [33] etc. The chitosan/CNT hybrid nanocomposites were reported to be able to be applied for vapor sensors, that will be discussed in more detail in the section 5.1 …”

“…One more interesting applications of polymer based hybrid nanocomposits are for the vapor sensors from CS/CNT hybrid nanocomposites . We prepared hybrid nanocomposite films consisting of CS grafted (CNT‐CS) and CS‐copolycaprolactone grafted (CNT‐CS‐PCL) multiwalled carbon nanotubes(MWCNT) using a spray layer‐by‐layer technique.…”

Polypyrrole/Metal Sulphide Hybrid Nanocomposites: Synthesis, Characterization and Room Temperature Gas Sensing Properties

“…Selection of appropriate nanomaterial for a CP is crucial to the ultimate application of the resulting nanocomposites, which is generally a result of the synergistic effect between the CP and the nanomaterial. 5,7,[12][13][14] Using nanotechnology, various macromolecules and nanomaterials have been used for gas sensing purposes 15,16 and amongst them metal oxides 17,18 and CPs 19 are most widely used. A silver nanocrystal has been reported as a promoter for carbon nanotube-based gas sensors at room-temperature.…”