Poly-3-hexylthiophene based organic field-effect transistor: Detection of low concentration of ammonia

The soluble poly-3-hexylthiophene (P3HT) based organic field effect transistors (OFETs) are fabricated and sensitivity of the device to ammonia vapour at room temperature is subsequently tested. The performance parameters of the OFET in air, water vapour and ammonia have been studied in order to explore the potential of this device as an ammonia sensor. The device parameters like drain–source current, mobility and threshold voltage are found to change significantly when the device is exposed to various concentrations of ammonia. The P3HT based OFET shows excellent response to ammonia in the range of 0.1–25 ppm at room temperature.