Sensors (Jul 2021)

Modeling the Conductivity Response to NO<sub>2</sub> Gas of Films Based on MWCNT Networks

  • Ada Fort,
  • Marco Mugnaini,
  • Enza Panzardi,
  • Anna Lo Grasso,
  • Ammar Al Hamry,
  • Anurag Adiraju,
  • Valerio Vignoli,
  • Olfa Kanoun

DOI
https://doi.org/10.3390/s21144723
Journal volume & issue
Vol. 21, no. 14
p. 4723

Abstract

Read online

This work proposes a model describing the dynamic behavior of sensing films based on functionalized MWCNT networks in terms of conductivity when exposed to time-variable concentrations of NO2 and operating with variable working temperatures. To test the proposed model, disordered networks of MWCNTs functionalized with COOH and Au nanoparticles were exploited. The model is derived from theoretical descriptions of the electronic transport in the nanotube network, of the NO2 chemisorption reaction and of the interaction of these two phenomena. The model is numerically implemented and then identified by estimating all the chemical/physical quantities involved and acting as parameters, through a model fitting procedure. Satisfactory results were obtained in the fitting process, and the identified model was used to further the analysis of the MWCNT sensing in dynamical conditions.

Keywords