Fluorinated Alcohol-Processed N-Type Organic Electrochemical Transistor with High Performance and Enhanced Stability

Abstract

Tuning the film morphology and aggregated structure is a vital means to improve the performance of the mixed ionic–electronic conductors in organic electrochemical transistors (OECTs). Herein, three fluorinated alcohols (FAs), including 2,2,2-trifluoroethanol (TFE), 1,1,1,3,3,3-hexafluoroisopropanol (HFIP), and perfluoro-tert-butanol (PFTB), were employed as the alternative solvents for engineering the n-type small-molecule active layer gNR. Remarkedly, an impressive μC* of 5.12 F V–1 cm–1 s–1 and a normalized transconductance of 1.216 S cm–1 are achieved from the HFIP-fabricated gNR OECTs, which is three times higher than that of chloroform. The operational stability has been significantly enhanced by the FA-fabricated devices. Such enhancements can be ascribed to the aggregation-induced structural ordering by FAs during spin coating, which optimizes the microstructure of the films for a better mixed ion and electron transport. These results prove the huge research potential of FAs to improve OECT materials’ processability, device performance, and stability, therefore promoting practical bio-applications.

J‐Type Self‐Assembled Supramolecular Polymers for High‐Performance and Fast‐Response n‐Type Organic Electrochemical Transistors

“…f) Comparison of the τ on and µC* values of TDPP‐RD‐G7 with other reported small‐molecule OECT materials. [ 40,42–46 ]…”

“…[ 38,39 ] Because of these features, more and more efforts have been devoted to exploring small‐molecule OECT materials. [ 40–46 ] Ginger et al chose fullerenes as the building block and reported fullerene derivatives with ethylene glycol (EG) side chains (C60‐TEG), which shows a high µC* value of 7 F cm −1 V −1 s −1 with no response time data. [ 40 ] Yue et al introduced rigid multi‐component fused‐ring to enhance the OECT performance, leading to good solid–state molecular packing and improved µC* of 10.3 F cm −1 V −1 s −1 and response speeds (τ on /τ off ) of 439/84 ms.…”

Ion Size-Dependent Electrochromism in Air-Stable Napthalenediimide-Based Conjugated Polymers

“…CPs offer incentives like precise control of color hue, saturation, brightness, and intensity by directly manipulating the redox nature of the backbone . Although the appropriate choice of donor–acceptor units and varying comonomer feed ratios have been shown to alter the optical, redox, and electrochromic performance of the polymer, , these design strategies are predominantly used to facilitate electronic charge transport.…”

“…Organic mixed-ionic electronic conductors (OMIECs) based on π-conjugated polymers (CPs) have attracted significant interest as electrode materials in energy storage devices due to the tunability of their electronic energy levels, ionic and electronic transport properties, and solution processability . However, most OMIECs reported in the literature are p-type CPs involving anion transport, while n-type OMIECs are studied less frequently . A majority of n-type CPs are prone to degrade in a doped state upon exposure to ambient conditions because their lowest unoccupied molecular orbitals (LUMO) are not sufficiently low enough to avoid water and oxygen reduction reactions, as shown in Figure S21. − However, the development of n-type materials is crucial for a variety of electrochemical applications such as light-emitting electrochemical cells (LEECs), electrochemical transistors (OECTs), ion pumps, bioelectronics, and electrochromic devices (ECDs) .…”

“…1 However, most OMIECs reported in the literature are p-type CPs involving anion transport, while n-type OMIECs are studied less frequently. 2 A majority of n-type CPs are prone to degrade in a doped state upon exposure to ambient conditions because their lowest unoccupied molecular orbitals (LUMO) are not sufficiently low enough to avoid water and oxygen reduction reactions, as shown in Figure S21. 3−5 However, the development of n-type materials is crucial for a variety of electrochemical applications such as light-emitting electro-chemical cells (LEECs), 6 electrochemical transistors (OECTs), 7 ion pumps, 8 bioelectronics, 9 and electrochromic devices (ECDs).…”