Realization of an Ultrasensitive and Highly Selective OFET NO2 Sensor: The Synergistic Combination of PDVT-10 Polymer and Porphyrin–MOF

• Published in: ACS applied materials & interfaces Vol. 12; no. 16; pp. 18748 - 18760
• Main Authors: Yuvaraja, Saravanan, Surya, Sandeep G, Chernikova, Valeriya, Vijjapu, Mani Teja, Shekhah, Osama, Bhatt, Prashant M, Chandra, Suman, Eddaoudi, Mohamed, Salama, Khaled N
• Format: Journal Article
• Language: English
• Published: American Chemical Society 22.04.2020
• Subjects: NO2 sensor; organic field-effect transistor; conjugated polymer; heterojunction; metal−organic framework
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.0c00803

Organic field-effect transistors (OFETs) are emerging as competitive candidates for gas sensing applications due to the ease of their fabrication process combined with the ability to readily fine-tune the properties of organic semiconductors. Nevertheless, some key challenges remain to be addressed, such as material degradation, low sensitivity, and poor selectivity toward toxic gases. Appropriately, a heterojunction combination of different sensing layers with multifunctional capabilities offers great potential to overcome these problems. Here, a novel and highly sensitive receptor layer is proposed encompassing a porous 3D metal–organic framework (MOF) based on isostructural-fluorinated MOFs acting as an NO2 specific preconcentrator, on the surface of a stable and ultrathin PDVT-10 organic semiconductor on an OFET platform. Here, with this proposed combination we have unveiled an unprecedented 700% increase in sensitivity toward NO2 analyte in contrast to the pristine PDVT-10. The resultant combination for this OFET device exhibits a remarkable lowest detection limit of 8.25 ppb, a sensitivity of 680 nA/ppb, and good stability over a period of 6 months under normal laboratory conditions. Further, a negligible response (4.232 nA/%RH) toward humidity in the range of 5%–90% relative humidity was demonstrated using this combination. Markedly, the obtained results support the use of the proposed novel strategy to achieve an excellent sensing performance with an OFET platform.