Electrolyte‐gated organic field‐effect transistors (EGOFETs) are gaining interest for application in bioelectronic devices. However, robust performance in terms of charge‐carrier mobility, on‐to‐off drain current ratio (Ion/Ioff), and turn‐on speed are required for real application. Here, donor‐acceptor (D‐A) conjugated polymers, namely poly[2,5‐(2‐octyldodecyl)‐3,6‐diketopyrrolopyrrole‐alt‐5,5‐(2,5‐di(thien‐2‐yl)thieno[3,2‐b]thiophene)] (PDPPDTT) and indacenodithiophene‐co‐benzothiadiazole (PIDTBT), are evaluated in EGOFETs. The operational performance of these materials is compared to that of the well‐established conjugated polymer, poly[2,5‐bis(3‐hexadecylthiophen‐2‐yl)thieno[3,2‐b]thiophene] (PBTTT). The effective mobility extracted for the PDPPDTT (0.18 cm2 V−1 s−1), and PIDTBT (0.16 cm2 V−1 s−1) devices is almost double that of the PBTTT (0.10 cm2 V−1 s−1) based device and the Ion/Ioff is one ((PDPPDTT): 3 × 103) or two ((PIDTBT): 2 × 104) orders of magnitude higher than that of PBTTT (2 × 102) devices. The extracted values compare favorably to those of the highest performing EGOFETs and EGOFETs based on the D‐A polymers turn from off to on state two to ten times faster than the analogous PBTTT device with an improved subthreshold swing. These results show that D‐A polymers with a planar conjugated backbone enable the development of robust EGOFETs that are well appropriate for applications in bioelectronic devices.

Rapid, large-scale, and low-cost coating methods that enable precise control of the crystal growth of organic semiconductors are essential to deliver high-performance devices that are robust and reproducible. In this work, a novel method is presented based on a gas blow coating technique, enabling the deposition of thin films of organic semiconductors, whose morphology can be optimized by adjusting the deposition parameters. We demonstrate the deposition of aligned single crystals of 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) and 2,7-dioctyl[1]benzothieno[3,2- b ][1]benzothiophene (C8-BTBT) by gas blow coating and their use as active layers in organic field-effect transistor (OFET) devices. The OFETs of TIPS-pentacene and C8-BTBT have charge mobilities of 0.15 and 1.4 cm 2 V –1 s –1 , respectively, with low threshold voltages and on/off ratios exceeding 10 5 . This coating method can also be extended to polymeric semiconductors: films based on poly(3-hexylthiophene) and poly[2,5-(2-octyldodecyl)-3,6-diketopyrrolopyrrole- alt -5,5-(2,5-di(thien-2-yl)thieno[3,2- b ]thiophene)] are realized, establishing gas blow coating as a novel and efficient technique for the deposition of thin films of organic semiconductors.

An Interdigitated array Electrode sensor (IES) is used for real-time monitoring of the crystallization dynamics of organic molecules, achieving a temporal resolution of 15 ms.

Quantitative measurements of molecular dynamics at the solid–liquid interface are of crucial importance in a wide range of fields, such as heterogeneous catalysis, energy storage, nanofluidics, biosensing, and crystallization. In particular, the molecular dynamics associated with nucleation and crystal growth is very challenging to study because of the poor sensitivity or limited spatial/temporal resolution of the most widely used analytical techniques. We demonstrate that electrolyte-gated organic field-effect transistors (EGOFETs) are able to monitor in real-time the crystallization process in an evaporating droplet. The high sensitivity of these devices at the solid–liquid interface, through the electrical double layer and signal amplification, enables the quantification of changes in solute concentration over time and the transport rate of molecules at the solid–liquid interface during crystallization. Our results show that EGOFETs offer a highly sensitive and powerful, yet simple approach to investigate the molecular dynamics of compounds crystallizing from water.

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