Journal Article

Efficient N‐Type Organic Electrochemical Transistors and Field‐Effect Transistors Based on PNDI‐Copolymers Bearing Fluorinated Selenophene‐Vinylene‐Selenophenes

Fazzi, Daniele, Bui, Thanh‐Tuan, Ludwigs, Sabine, Ursel, Sarah, Zhang, Youcheng, Un, Hio‐Ieng, Roesner, Stefan, Marathianos, Arkadios, Sirringhaus, Henning, Sun, Xiuming, Manikandan, Suraj, Peralta, Sébastien, Xiao, Mingfei, Andreasen, Jens Wenzel, Kim, Jongho, Ren, Xinglong, Wang, Suhao, Town, James

2023

Overview

n‐Type organic electrochemical transistors (OECTs) and organic field‐effect transistors (OFETs) are less developed than their p‐type counterparts. Herein, polynaphthalenediimide (PNDI)‐based copolymers bearing novel fluorinated selenophene‐vinylene‐selenophene (FSVS) units as efficient materials for both n‐type OECTs and n‐type OFETs are reported. The PNDI polymers with oligo(ethylene glycol) (EG7) side chains P(NDIEG7‐FSVS), affords a high µC* of > 0.2 F cm−1 V−1 s−1, outperforming the benchmark n‐type Pg4NDI‐T2 and Pg4NDI‐gT2 by two orders of magnitude. The deep‐lying LUMO of −4.63 eV endows P(NDIEG7‐FSVS) with an ultra‐low threshold voltage of 0.16 V. Moreover, the conjugated polymer with octyldodecyl (OD) side chains P(NDIOD‐FSVS) exhibits a surprisingly low energetic disorder with an Urbach energy of 36 meV and an ultra‐low activation energy of 39 meV, resulting in high electron mobility of up to 0.32 cm2 V−1 s−1 in n‐type OFETs. These results demonstrate the great potential for simultaneously achieving a lower LUMO and a tighter intermolecular packing for the next‐generation efficient n‐type organic electronics. Novel PNDI‐based polymers bearing fluorinated selenophene‐vinylene‐selenophene (FSVS) are synthesized. The glycolated P(NDIEG7‐FSVS) with a deep‐lying LUMO of −4.63 eV gives an ultra‐low threshold voltage of 0.16 V, yielding a µC* > 0.2 F cm−1 V−1 s−1 in n‐type OECTs; the alkylated P(NDIOD‐FSVS), with a low Urbach energy of 36 meV and a low activation energy of 39 meV, exhibits electron mobility of > 0.3 cm2 V−1 s−1 in n‐type OFETs.

• Publisher: John Wiley & Sons, Inc,Wiley Open Access,John Wiley and Sons Inc,Wiley
• Subject: Chemical Sciences / intermolecular packing / Investigations / Medical equipment / mixed ionic–electronic conductors / n‐type conjugated polymers / organic electrochemical transistors / organic field‐effect transistors / Polymer films / Polymers / Transistors