Abstract
We report an organic field-effect transistor (OFET)-based sensor made from printable materials with an unusually high sensitivity of 0.5 ppm v/v for ammonia and with limit of detection on the order of 0.1 ppm v/v. The device developed has a polyethylene terephthalate (PET) substrate, bottom contacts, and poly (3,3⌄-didodecylquaterthiophene) (PQT-12) cast from 4 mg/mL cholorobenzene solution as active semiconductor. The fabrication process is simplified by replacing the gate electrode and dielectric deposition steps with the introduction of static charges on the back surface of the PET substrate by corona charging, a procedure that is adaptable to roll-to-roll processing. Hydrophobic polymers applied to the back surface stabilize this charge, providing evidence for their activity at that location. In the proposed sensor, these static charges are used as a static gate, reducing the OFET architecture to a chemiresistor. The sensor is selective for ammonia over common organic solvent vapors, and the response is generally reversible. The device also demonstrates memory behavior required for dosimetric sensors when kept at low temperature (4 °C to -30 °C). A converse response from an n-channel semiconductor is also reported.
Original language | English (US) |
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Pages (from-to) | 3221-3230 |
Number of pages | 10 |
Journal | Organic Electronics |
Volume | 15 |
Issue number | 11 |
DOIs | |
State | Published - Nov 2014 |
Keywords
- Ammonia sensor
- Corona charging
- Organic field effect transistor
- PQT-12
- Poly(ethyleneterephthalate)
- Silver ink
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Biomaterials
- General Chemistry
- Condensed Matter Physics
- Materials Chemistry
- Electrical and Electronic Engineering