Soluble polythiophene derivatives for NO2 sensing applications

Different soluble polythiophenes including poly(3-octylthiophene, poly(3-octylthiophene-co-thienylethanol) copolymers and c14-alkylated poly(3,4-ethylenedioxythiophene methanol) were first synthesized and characterized by GPC, NMR, FT-IR and UV-visible spectroscopies. Films were deposited by spray coating on an especially designed interdigitated array of electrodes. Film responses during NO2 pulses were monitored by conductivity measurements. The effects of chemical structure and storage conditions on gas sensitivity and reversibility are discussed.