Carbon nanotube/PMMA composite thin films for gas-sensing applications

Abstract

The design and development of composite thin films of polymethylmethacrylate (PMMA) with multiwalled carbon nanotubes (CNTs) and surface-modified multiwalled carbon nanotubes (f-CNTs) for gas-sensing applications are presented in this paper. The responses of these composites for different organic vapors were evaluated by monitoring the change in the resistance of thin films of composite when exposed to gases like dichloromethane, chloroform, acetone, methanol, ethyl acetate, toluene and hexane. It was observed that the f-CNT/PMMA composite showed a higher response. There was an increase in resistance of the order of 10 2 -10 3 , due to surface modification, when exposed to dichloromethane, chloroform and acetone. The sensing mechanism is explained on the basis of volume expansion and polar interaction of various vapors on the CNT surface.

Carbon Nanotube-Based Sensors

“…Carbon Nanotube-Based Sensors [114], [115], [117], CO [137], [147], [119], [136], [137], [174], [175] [143], [152], [153] [114], [139], [150], Glucose [112], [135], [152], [163], [165], [140], [142], [176] [146], [149], [168] [160] Other chemical [116], [118], pesticides vapors [129], [130], [131], [137], [155], [157], [173] such as sensors, biosensors, and biological fuel cells and reactors. Several types of carbon nanotube sensors were reviewed in this section.…”

“…198 By detecting the concentration of these chemicals, the quality of meat can be controlled. Philip et al 173 reported a CNT/Polymer gas sensor that can detect different organic vapors including ethyl acetate. The sensing material in this gas sensor is CNT/polymethylmethacrylate (PMMA) composite thin film.…”

Sensing of Acetone Vapours using Polymer Composite

“…These devices should be cheap, reagentless and able to quantify the levels of gases in a rapid manner, at room temperature with low power consumption 5 . The room temperature gas sensing property is very attractive for many applications 6,7 . Acetone is a commonly used chemical reagent in industry, For instance it is used to dissolve plastics, purify paraffin, dehydrate tissues and for pharmaceutical applications.…”

Multinanosensors Based on MWCNTs and Biopolymer Matrix - Production and Characterization

“…However, since the discovery of carbon nanotubes (CNTs) in 1991, CNTs have been the focus of intensive research due to their superior characteristics such as chemical, thermal, and mechanical stability, semiconductive properties and functionalization capability [1][2][3]. These properties make them favorable candidates for active building elements in gas sensors [4][5][6], exploiting their sensing nature even at room temperatures [7,8]. The potential of CNTs as sensing element is based not only on these extraordinary properties, but also on their hollow structure and high surface-to-volume ratio (A/V) [9][10][11].…”

“…Quite a few of these authors call upon percolation theory in explaining the electrical changes of insulating polymer matrix in which CNTs are dispersed [31][32][33][34]. Incorporation of CNTs in a polymer matrix is found to reduce the percolation threshold to a very low filler volume, and amorphous poly(methyl methacrylate) PMMA has been proven an easy to process polymer which fulfills this prerequisite (avoiding potential complications related to the crystallization) [35,36].…”