Organic Thin-Film Transistors as Gas Sensors: A Review

• Published in: Materials Vol. 14; no. 1; p. 3
• Main Authors: Cavallari, Marco Roberto, Pastrana, Loren Mora, Sosa, Carlos Daniel Flecha, Marquina, Alejandra Maria Rodriguez, Izquierdo, José Enrique Eirez, Fonseca, Fernando Josepetti, Amorim, Cleber Alexandre de, Paterno, Leonardo Giordano, Kymissis, Ioannis
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 22-12-2020; MDPI AG
• Subjects: flexible electronics; gas sensors; organic field- effect transistors; organic semiconductors; organic thin-film transistors; Review; flexible electronics; organic semiconductors; organic thin-film transistors; organic field- effect transistors; gas sensors
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma14010003

Organic thin-film transistors (OTFTs) are miniaturized devices based upon the electronic responses of organic semiconductors. In comparison to their conventional inorganic counterparts, organic semiconductors are cheaper, can undergo reversible doping processes and may have electronic properties chiefly modulated by molecular engineering approaches. More recently, OTFTs have been designed as gas sensor devices, displaying remarkable performance for the detection of important target analytes, such as ammonia, nitrogen dioxide, hydrogen sulfide and volatile organic compounds (VOCs). The present manuscript provides a comprehensive review on the working principle of OTFTs for gas sensing, with concise descriptions of devices' architectures and parameter extraction based upon a constant charge carrier mobility model. Then, it moves on with methods of device fabrication and physicochemical descriptions of the main organic semiconductors recently applied to gas sensors (i.e., since 2015 but emphasizing even more recent results). Finally, it describes the achievements of OTFTs in the detection of important gas pollutants alongside an outlook toward the future of this exciting technology.