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Naphthalene diimide-based polymeric semiconductors. Effect of chlorine incorporation and n-channel transistors operating in water

  • Gi-Seong Ryu (a1), Zhihua Chen (a2), Hakan Usta (a3), Yong-Young Noh (a1) (a4) and Antonio Facchetti (a2) (a5)...


We demonstrate here the design, synthesis and characterization of two new chlorinated polymers, P(NDI2HD–T2Cl2) and P(NDI2OD–T2Cl2) based on N,N′-difunctionalized naphthalene diimide (NDI) and 3,3′-dichloro-2,2′-bithiophene (T2Cl2) moieties. Our results indicate that organic thin-film transistors (OTFTs) based on these new chlorinated polymers exhibit electron mobilities approaching 0.1 cm2V−1s−1 (I on:I off ~ 106–107), with far less ambipolarity due to their lower highest occupied molecular orbital energies, and they are more stable under deleterious high-humidity conditions (RH ~ 60%) and upon submersion in water, compared with those fabricated with the parent non-chlorinated polymers. In addition, OTFTs fabricated with the new chlorinated polymers exhibit excellent operational stabilities with <3% degradations upon bias-stress test.


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Address all correspondence to Antonio Facchetti, Yong-Young Noh, Hakan Usta at,,


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