Molecular Dynamics Analysis of Experimental Results for an Optimal Indium Oxide Dopant Concentration in Polyaniline for Effective Formaldehyde Sensing

Polyaniline (PANI) doped with indium oxide (IO) is an excellent gas sensing material for detecting formaldehyde (F). It is proposed that an optimal weight percentage of IO exists in PANI composite that can exhibit higher sensitivity to F. To study the effect of the level of IO concentration in PANI, molecular dynamics (MD) simulations are performed. IO concentrations range from 0% (pure PANI) to 10% (w/w) in the PANI composite, and the corresponding weight percent of F penetrant loading is determined. A parabolic trend is observed where the sensitivity of PANI-IO sensing material reaches a maximum and then decreases with a further increase in dopant concentration. MD simulation trends agree with experimental results. The findings from this study are not only crucial for formaldehyde detection but can also be extended to the detection of other volatile organic compounds.