Fully ink-jet printed gas sensors based on organic field-effect transistors

The development of gas sensors with a low limit of detection is a challenging task, which is actual for many applications requiring complex gas mixture analysis. Application of organic field-effect transistors (OFETs) as sensing elements is very promising due to a strong dependence of their electrical parameters on the environment composition. The OFET layers of different architectures can be fabricated straight forward by ink-jet printing technology, however no fully-printed gas sensors based on OFETs have been reported yet. Here, we describe the first example of such sensors and their sensory properties towards low concentrations of various toxic gases such as nitrogen oxide, hydrogen sulfide or ammonia. Comparison with monolayer OFET sensors allowed to make some suggestions about the mechanism of their sensing. The sensors demonstrate a great potential of sensory devices based on the printed OFETs, while the sensory properties estimation shows a few issues to be solved before the widespread use of such devices.