Improvement of sensing properties for polymer based gas sensors via host-guest principles

Abstract

This study aimed at improving the sensing properties of polymer-based gas sensors by controlling the surface adsorption. For this purpose, a polymer was produced as a Langmuir-Blodgett (LB) thin film chemical gas sensor element. The polymer material used was characterized by FTIR, H-1 and C-13 NMR analyses. All LB thin film layers were characterized by UV-Vis spectroscopy, scanning electron microscopy (SEM), quartz crystal microbalance (QCM) and atomic force microscopy (AFM) techniques. The polymeric chemical sensor was exposed to four different harmful organic vapours using QCM. The diffusion coefficients were calculated for each organic vapour using the short time approximation of the Fick's second diffusion law. The results showed that the response of the polymeric LB films to the harmful vapours was large, fast and reversible and the diffusion coefficients were found to increase in the order dichloromethane, chloroform, benzene and toluene at room temperature. Graphic abstract