Ether-Functionalized Ammonium Salts to Enhance Electron Transport in n-Type Conjugated Polymers

초록

Conjugated polymers (CPs) are promising solution-processable semiconductors for fabricating next-generation electronic devices. For the realization of highly performing CP-based electronics, ionic additives have been considered to tune the morphology and charge transport of conjugated polymers. However, achieving high-performance n-type CPs remains challenging because of their limited compatibility with ionic additives. Here, an ether-functionalized ammonium salt (EGBr) was introduced as an additive for the benchmark n-type polymer, N2200, to improve miscibility and molecular ordering. The ether functionality facilitated homogeneous film formation, resulting in an enhanced electron mobility (µ<inf>e</inf>) of 1.09 cm2 V−1 s−1, compared with 0.510 cm2 V−1 s−1 for the alkyl-based additive (HptBr) and 0.272 cm2 V−1 s−1 for the control. When employed as an electron-transporting layer in organic photodiodes, EGBr-incorporated N2200 enabled efficient electron extraction and suppressed interfacial recombination, yielding a shot-noise-limited specific detectivity (D*<inf>shot</inf>) of 2.11 × 1013 cm Hz0.5 W−1, outperforming the HptBr-incorporated film (8.31 × 1012 cm Hz0.5 W−1) and the control (3.79 × 1012 cm Hz0.5 W−1). These results highlight that incorporating ether-functionalized ionic additives is an effective strategy to enhance charge transport in n-type CPs and the performance of organic optoelectronic devices. © 2026 Wiley-VCH GmbH.

키워드