Electrical response of electrospun PEDOT-PSSA nanofibers to organic and inorganic gases

Electrospun isolated nanofibers of poly(3,4-ethylenedioxythiophene) doped with (poly styrene sulfonic acid)-PEDOT-PSSA were used to sense vapors of several aliphatic alcohols. Due to the large surface to volume ratio and small quantity of active material used in their fabrication, these sensors have a similar or faster response time when compared to alcohol sensors based on PEDOT. Increasing the size of the alcohol molecule leads to longer response times, which is attributed to slower diffusion of the larger molecule into the polymer. The sensors were annealed in air at 70 °C and used to sense NH3, HCl and NO2 gas. The response time for NH3 was faster than HCl, and the sensors showed a large initial response to NO2 at room temperature which is very desirable, as some NO2 gas sensors only operate at elevated temperatures. Electrospinning is a simple and inexpensive method of preparing PEDOT-PSSA nanofibers making it an attractive technique to fabricate polymer based low cost, rapid response and reusable gas sensors.