One-dimensional variable range charge carrier hopping in polyaniline–tungsten oxide nanocomposite-based hydrazine chemiresistor

• Published in: Applied physics. A, Materials science & processing Vol. 127; no. 7
• Main Author: Chaudhary, Vishal
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2021; Springer Nature B.V
• Subjects: Applied physics; Chains; Characterization and Evaluation of Materials; Charge transport; Condensed Matter Physics; Current carriers; Direct current; Hopping conduction; Hydrazines; Low temperature; Machines; Manufacturing; Materials science; Nanocomposites; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Polyanilines; Processes; Room temperature; Surfaces and Interfaces; Thermal conductivity; Thin Films; Three dimensional models; Tungsten oxides; DC charge transport; Variable range hopping; Chemiresistor; Hydrazine; Polyaniline–tungsten oxide nanocomposite
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-021-04690-8

Low-temperature direct current charge transport mechanism of charge carriers in polyaniline–tungsten oxide (PAN-WO 3 ) nanocomposite has been investigated. Charge transport in pristine PAN was found to govern by Mott’s three-dimensional variable range hopping (3-D VRH) model. However, the inclusion of WO 3 in nanocomposite shifts the dimension of hopping from 3-D to 1-D. The room-temperature conductivity of PAN-WO 3 nanocomposite (5.55 × 10 –3 S/cm) was also found to be enhanced compared to pristine PAN (1.27 × 10 –5 S/cm). The reasons for crossover in hopping dimensionality and enhanced conductivity of PAN-WO 3 nanocomposite have been explained in terms of Mott’s parameters, i.e., small hopping radius, lower hopping energy, high inter-chain distance, and prominent intra-chain transport. Furthermore, PAN-WO 3 exhibited enhanced reversible sensing behaviour (27%) towards 10 parts per million of hydrazine at room temperature compared to that of pristine PAN (12%). Enhanced sensing characteristics of PAN-WO 3 nanocomposite can be attributed to its higher conductivity and prominent intra-chain unidirectional charge transport. Present communication opens a new window for energy-saving, eco-friendly, cost-effective, recoverable and reproducible, easily processable and efficient PAN-WO 3 nanocomposite-based hydrazine detecting device.