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

Abstract

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.

Molecular Engineering of Porphyrin‐Tapes/Phthalocyanine Heterojunctions for a Highly Sensitive Ammonia Sensor

“…[ 5 ] Another application area of MPor is chemosensing, [ 6 ] in which interactions with a chemical analyte modifies the physical properties of MPor film that can be transduced into a measurable signal. Based on the nature of signal transductions, MPor‐based optical, acoustic, magnetic, and electrical chemosensors have been developed [ 7 ] to detect myriad of species such as redox gases, [ 8 ] volatile organic compounds, [ 9 ] and inorganic biochemical species. [ 10 ] Particularly, MPor chemosensors based on electrical transductions such as chemiresistors, ChemFet, and conductometric sensors have drawn interests exploiting the semiconducting nature of MPor, which can be effectively tuned by adding substituents to its macrocyclic periphery or ligands at the metal center.…”

Semi-transparent graphite films growth on Ni and their double-sided polymer-free transfer

“…The chemi-resistance sensor (an inter-digitated electrode chip) was wire-bonded to a customised printed circuit board 73 , and the resistance was extracted in transient mode. The board, with the mounted device, was connected to contact leads and placed inside the gas-sensing chamber 74 .…”

Recent advances in energy-saving chemiresistive gas sensors: A review

“…Nowadays, the detection of dangerous gases is becoming increasingly important in different industries, indoor and outdoor air quality monitoring, public safety, mines, and so on [ [8] , [9] , [10] , [11] ], As a result, numerous sensing techniques, such as the electrochemical [ 12 ], optical fiber [ 13 ], quartz crystal microbalance (QCM) [ 14 ] and capacitive [ 15 ] techniques, have been applied for this purpose. However, most of these techniques have disadvantages such as relatively high price, low sensitivity and selectivity, sophisticated design, and a need for additional equipment; some even lack portability [ 16 ]. Among them, metal oxide semiconductor (MOS) gas sensors, working on the basis of changes in resistance in the presence of a target gases, have attracted great attention and have become a hot research topic [ 17 ] because of their numerous and unique characteristics, such as high sensitivity, short response/recovery time, ease of fabrication, high stability, simple operation and low price [ 18 , 19 ].…”