Improving the selectivity to polar vapors of OFET-based sensors by using the transfer characteristics hysteresis response

Sensing of polar volatile organic compounds by generic organic-field-effect transistors has been achieved by monitoring both, the drain current at a fixed gate voltage and the charge carrier mobility. In this paper we show that the hysteresis of the transfer-characteristics of P3HT-based OFETs can be used as an additional sensing parameter for the detection of polar vapors. The response of the hysteresis to polar vapors is marked by a reversible increase at a time-scale similar to the previously reported parameters. By supplementing the responses of on-current and mobility with the hysteresis-response, an improvement of the device selectivity to ethanol and acetone vapor is achieved.