Syndiotactic polystyrene thin film as sensitive layer for an optoelectronic chemical sensing device

In this work the performance of an optoelectronic sensor system able to measure the concentration of organic analytes, in aqueous environment was analyzed. Syndiotactic polystyrene (sPS) in the nanoporous crystalline δ form was here used as sensitive polymeric layer due to its high sorption properties towards chlorinated and aromatic compounds. In particular, a thin semi-crystalline sPS film with crystalline nanoporous δ form was cast on the cleaved end of a standard fiber optic and measurements of reflectivity as the analyte was sorbed by the polymer were carried out allowing on-line detection of even very low concentrations (in the range of few ppm) of chloroform and toluene in water. The refractometer performance was compared with that of a classical resonant quartz-crystal microbalance sensor (QCM), using the same polymer as sensing element.