Light‐Insensitive Organic Field‐Effect Transistors with n‐Type Conjugated Polymers Containing Dinitrothiophene Units

Abstract

Here, it is reported that organic field‐effect transistors (OFETs) with n‐type conjugated polymer, poly[{2,5‐bis‐(2‐octhyldodecyl)‐3,6‐bis‐(thien‐2‐yl)‐pyrrolo[3,4‐c]pyrrole‐1,4‐diyl}‐co‐{2,2′‐(3,4‐dinitrothiophene)]‐5,5′‐diyl}] (PODTPPD‐DNT), can be operated without large disturbance by surrounding light. The PODTPPD‐DNT polymer synthesized via the Stille coupling reaction could act as a channel layer for n‐channel OFETs. Although the PODTPPD‐DNT polymer shows a broad optical absorption from ultraviolet to near‐infrared parts up to 1000 nm, the OFETs with the PODTPPD‐DNT channel layers do not almost respond to monochromatic (520 and 780 nm) and white light. The reason is assigned to the exciton quenching effect by two nitro groups in the polymer chain. The semitransparent OFETs with the 20 nm thick PODTPPD‐DNT channel layers are also almost light‐insensitive for operation under typical room light conditions.

A Centrosymmetric Organic Semiconductor with Donor–Acceptor Interaction for Highly Photostable Organic Transistors

“…The special D-A interaction with strong electron-withdrawing group is beneficial to occuring photoinduced charge transfer, which will further generate polaron in this system and facilitate the exciton quenching process in the aggregate state (Figure 4c; Figure S6, Supporting Information). [9,37,[39][40][41][42][43] However, the exciton quenching process of S-TT-TPA will be suppressed more efficiently, which might be originated from the looser packing motif (Figure 1b,c) and weaker intermolecular interaction than TFP-TT-TPA as predicted by theoretical calculation (Figure 5c-e). Therefore, for the photostable TFP-TT-TPA OFETs, after the formation of photogenerated excitons under irradiation, a large number of excitons will in the semiconductor layer.…”

High mobility n-type organic semiconductors with tunable exciton dynamics toward photo-stable and photo-sensitive transistors

“…(i) The introduction of halogen atoms could decrease the lowest unoccupied molecular orbitals (LUMO) levels, 24 which is beneficial to enhance the electronic affinity of molecules, and provides more short contacts between adjacent molecules compared to TAA-4P. 23 (ii) The introduction of small polar groups 25 (F atoms and chlorine atoms) could regulate the photo-stability/photo-sensitivity without destroying the transport properties.…”

DPP-based polymers with linear/branch side chain for organic field-effect transistors

“…In the past few decades, organic conjugated polymers have been widely used in the field of field-effect transistors due to their flexible molecular structures and good solubility ( Guo et al, 2013 ; Moon et al, 2018 ; Michael, 2021 ). In the late 1980s, the first organic field-effect tube made of polythiophene was developed for the first time ( Cui et al, 2018 ; Zou et al, 2019 ).…”