π-Conjugated polymers derived from 2,5-bis(2-decyltetradecyl)-3,6-di(selenophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione for high-performance thin film transistors

• Published in: Polymer chemistry Vol. 6; no. 10; pp. 1777 - 1785
• Main Authors: Lee, Tae Wan, Lee, Dae Hee, Shin, Jicheol, Cho, Min Ju, Choi, Dong Hoon
• Format: Journal Article
• Language: English
• Published: 01.01.2015
• ISSN: 1759-9954; 1759-9962
• DOI: 10.1039/C4PY01536C

Novel 2,5-bis(2-decyltetradecyl)-3,6-di(selenophen-2-yl)pyrrolo[3,4- c ]pyrrole-1,4(2 H ,5 H )-dione (DSDPP)-containing conjugated polymers with different donor monomers were synthesized via a Pd(0)-catalyzed Stille coupling reaction. Solubilized 2-decyltetradecyl (DT) groups were tethered to the N-atoms in diketopyrrolopyrrole (DPP). As electron-donating units, bithiophene (BT) and a π-extended ( E )-2-(2-(thiophen-2-yl)vinyl)thiophene (TVT) were introduced into the polymer backbone. Besides thiophene-based monomers, biselenophene (BS) and ( E )-2-(2-(selenophen-2-yl)vinyl)selenophene (SVS) were also copolymerized with the same DSDPP-based monomer. DSDPP-BS and DSDPP-SVS copolymers exhibited higher hole mobilities in thin film transistors (TFTs) than the corresponding BT and TVT analogs. In particular, a TFT having a DSDPP-SVS copolymer-based active layer showed the highest hole mobility of ∼5.23 cm 2 V −1 s −1 and high current on/off ratios of ∼10 7 ; this indicates that the π-extended SVS significantly improves charge transport properties.