Organic n-Channel Transistors Based on [1]Benzothieno[3,2-b]benzothiophene–Rylene Diimide Donor–Acceptor Conjugated Polymers

Improving the charge-carrier mobility of conjugated polymers is important for developing high-performance, solution-processed optoelectronic devices. Although [1]benzothieno[3,2- b ]benzothiophene (BTBT) has been frequently used as a high-performance p-type small molecular semiconductor and employed a few times as a building block for p-type conjugated polymers, it has never been explored as a donor moiety for high-performance n-type conjugated polymers. Here, BTBT has been conjugated with either n-type perylene diimide (PDI) or naphthalene diimide (NDI) units to generate a donor–acceptor copolymer backbone, for the first time. Charge-transport measurements of organic field-effect transistors show n-type dominant behaviors, with the electron mobility reaching ∼0.11 cm 2 V –1 s –1 for PDI–BTBT and ∼0.050 cm 2 V –1 s –1 for NDI–BTBT. The PDI–BTBT mobility value is one of the highest among …