Rapid response and excellent recovery of a polyaniline/silicon carbide nanocomposite for cigarette smoke sensing with enhanced thermally stable DC electrical conductivity

Abstract

In this paper, we present an electrical conductivity based rapid response and excellent recovery cigarette smoke sensor based on polyaniline/silicon carbide (Pani/SiC) nanocomposite prepared by in-situ chemical oxidative polymerization technique in an acidic medium. The Pani/SiC nanocomposites and polyaniline (Pani) were characterized by using Fourier transform infrared spectroscopy, x-ray diffraction, scanning electron microscopy and transmission electron microscopy. Results indicated that the well ordered nanocomposites were successfully prepared. The morphology and electrical properties of the nanocomposites were influenced by the extent of loading of SiC nanoparticles. The as-prepared materials were studied for the change in their electrical conductivity on exposure to cigarette smoke followed by ambient air at room temperature. It was observed that Pani/SiC-3 nanocomposite shows eight times higher amplitude of conductivity change than Pani on exposure cigarette smoke followed by ambient air. The conductivity response in the carbon monoxide, ammonia and methanol was also measured. It was observed that the carbon dioxide (CO 2 ) shows low response while in the case of methanol and ammonia the significant responses are observed, suggesting the possibility of contribution of above gases towards response against cigarette smoke. The cigarette smoke also contains many other volatile chemicals such as polyaromatic hydrocarbon (PAH), nicotine, hydrogen cyanide (HCN) and formaldehyde which may also interacted with polarons/bipolarons of polyaniline leading to decreasing in conductivity.

Polythiophene/graphene/zinc tungstate nanocomposite: Synthesis, characterization, DC electrical conductivity and cigarette smoke sensing application

“…Conducting polymers (CPs)-based nanomaterials are one of the most competent in the field of chemical/gas/vapour sensors at room temperature. 1,7 -12 The nanocomposites of these CPs have been prepared by encapsulation or mixing of inorganic nanoparticles within their matrix. 8,9,11 There are several CPs, for instance polypyrrole, polythiophene (PTh) and polyaniline (Pani) and their nanocomposites, which have become the topic of massive interest in devising chemical/gas/vapour sensors, 1,13 -16 energy devices, 17,18 electronic and optical devices.…”

Graphene/Nickel Oxide-Based Nanocomposite of Polyaniline with Special Reference to Ammonia Sensing

“…The isothermal ageing stabilities of Pani, Pani/NiO, Pani/GN, and Pani@GN/NiO nanocomposites were calculated, as shown in Figure 7, by using the following equation: 13 where σ t is the electrical conductivity at time t and σ 0 is the electrical conductivity at time zero at experimental temperature. The as-prepared materials were examined for stability in terms of dc electrical conductivity retention with respect to time at different temperatures.…”

“…The cyclic ageing stabilities of Pani, Pani/NiO, Pani/GN, and Pani@GN/NiO nanocomposites were studied, as shown in Figure 8. 13 The relative electrical conductivity (σ r ) was calculated using the following equation:where σ T is the electrical conductivity (S/cm) at temperature T (°C) and σ 50 is the electrical conductivity (S/cm) at 50 °C, that is, at the beginning of each cycle.…”

“…The efficient gas sensing properties of Pani@GN/NiO may be attributed to the large surface area of Pani which anchored more adsorption and desorption of gaseous molecules as well as high polarons mobility due to the presence of GN, essential requirement for rapid response of any electrical conductivity-based sensor. 13 It is expected that the NiO embedded on GN sheets interacts with lone pairs of nitrogen atoms of Pani, thus increasing the number of polarons in Pani and creating a more number of active sites at a large surface area for the interaction of lone pairs of ammonia molecules to polarons of Pani. However, the detailed understanding on the role of NiO and GN sheets in the sensing mechanism of the Pani@GN/NiO nanocomposite requires further investigations on this aspect.…”

“…In order to improve the sensing performance of Pani, many efforts have been made by loading the noble metals, semiconductors, and other components to develop composite materials. 11−13 Recently, nickel oxide (NiO) nanoparticles have drawn considerable attention because of their low price, acceptable sensing properties, and good environmental stability. Researchers developed gas sensors based on NiO films which have demonstrated significant sensing properties.…”