Abstract
Electrolyte-gated transistors (EGTs) are typically limited to p-type operation, with stable n-type devices remaining scarce. In this study, we demonstrate high-performance n-type EGTs using a poly(benzimidazobenzophenanthroline) (BBL) polymer semiconductor gated by ionogel electrolytes. Electrochemical doping in BBL induces ion pathways in amorphous regions during initial doping, facilitating efficient electron transport. This yields exceptional device performance, including a geometry-normalized transconductance of 4.6 S cm−1, an ON/OFF ratio of ≈105, a product of electron mobility and volumetric capacitance (μC* ≈ 16.4 F cm–1 V–1 s–1), and minimal hysteresis (<0.1 V). These features surpass most reported n-type EGTs, demonstrating the importance of ion-driven electrochemical doping in BBL. Furthermore, we not only fabricate all-polymer complementary inverters, NAND, and NOR gates but also demonstrate flexible circuits by integrating n-type BBL and p-type polythiophene EGTs.
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Acknowledgements
This research was supported by Korea Basic Science Institute (National research Facilities and Equipment Center) grant funded by the Ministry of Education (2021R1A6C101A404), Korea Institute for Advancement of Technology (KIAT) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. P0017363), the National Research Foundation of Korea (NRF) grant funded by the Korean government (Ministry of Science and ICT, MSIT) (RS-2025-24523099), and Korea Research Institute of Chemical Technology (KRICT) Core Project (KS2621-20). This work was partially supported by the MRSEC program of the U.S. National Science Foundation (NSF) under Grant Number DMR-2011401.
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S.J.K. and D.H.P. contributed equally to this work. K.H.L., C.D.F., and K.G.C. conceived the idea and designed the experiments. S.J.K., D.H.P. and Y.N.L. performed device fabrication and characterization. M.S.K. and K.H. supported device characterization. S.J.K., K.G.C. and K.H.L. wrote the manuscript with input from C.D.F. and K.H. All authors contributed to discussions on the manuscript.
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Kim, S.J., Park, D.H., Lee, Y.N. et al. Sub-1V, flexible, all-polymer complementary logic circuits based on electrolyte-gated transistors. npj Flex Electron (2026). https://doi.org/10.1038/s41528-026-00530-y
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DOI: https://doi.org/10.1038/s41528-026-00530-y
