Detection of volatile organic sulfur compounds (VOSCs) by SAW sensor based on hydrogen-bond acidic polymers

Abstract

In this paper, PLF, LSFA and DKAP, three linear hydrogen-bond acidic (HBA) polymers synthesized in our laboratory and one commercial available hyperbranched HBA polymer HC were coated on 434 MHz surface acoustic wave (SAW) devices for rapid detection of volatile organic sulfur compounds (VOSCs). Sensitivity and selectivity of the polymer-coated sensors were studied by exposing to VOSCs in the concentration range of 1 mg/m3 to 49 mg/m3, as well as some common interference vapors at 10 mg/m3. High sensitivity and selectivity of these sensors to VOSCs are demonstrated. The sensitivities are attributed to the lone pair electrons in the sulfur atoms, which act as electron donors and facilitate the hydrogenbond formation between the analytes and the hydroxy groups of HBA polymers. The sensitive mechanism is further confirmed by the calculated results based on density functional theory.