Mixed conductors—materials that can efficiently conduct both ionic and electronic species—are an important class of functional solids. Here we demonstrate an organic nanocomposite that spontaneously forms when mixing an organic semiconductor with an ionic liquid and exhibits efficient room-temperature mixed conduction. We use a polymer known to form a semicrystalline microstructure to template ion intercalation into the side-chain domains of the crystallites, which leaves electronic transport pathways intact. Thus, the resulting material is ordered, exhibiting alternating layers of rigid semiconducting sheets and soft ion-conducting layers. This unique dual-network microstructure leads to a dynamic ionic/electronic nanocomposite with liquid-like ionic transport and highly mobile electronic charges. Using a combination of operando X-ray scattering and in situ spectroscopy, we confirm the ordered structure of the nanocomposite and uncover the mechanisms that give rise to efficient electron transport. These results provide fundamental insights into charge transport in organic semiconductors, as well as suggesting a pathway towards future improvements in these nanocomposites.
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We thank L. Richter for helpful discussions regarding X-ray scattering results, and E. Barks for assistance with ceramic polishing. T.J.Q. and G.L. acknowledge support from the National Science Foundation Graduate Research Fellowship Program under grant DGE-1656518. This material is based on work supported by the US Department of Energy (DOE), Office of Science, Office of Workforce Development for Teachers and Scientists, Office of Science Graduate Student Research (SCGSR) program. The SCGSR program is administered by the Oak Ridge Institute for Science and Education for the DOE under contract no. DE‐SC0014664. A.G. and A.S. acknowledge funding from the TomKat Center for Sustainable Energy at Stanford University. A.S. gratefully acknowledges financial support from the National Science Foundation award no. DMR 1808401. The use of Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the US DOE, Office of Science, Office of Basic Energy Sciences, under contract no. DE-AC02-76SF00515. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation under award ECCS-2026822. A.S. and T.J.Q. acknowledge financial support from the National Science Foundation and the Semiconductor Research Corporation, E2CDA award no. 1739795. We thank H. Celik and UC Berkeley’s NMR facility in the College of Chemistry (CoC-NMR) for spectroscopic assistance; the instrument used in this work is supported by the National Science Foundation under grant no. 2018784. D.M.H. acknowledges support from the Joint Center for Energy Storage Research, an Energy Innovation Hub funded by the US DOE, Office of Science, Basic Energy Sciences. I.M. acknowledges financial support from KAUST Office of Sponsored Research CRG10, by EU Horizon2020 grant agreement no. 952911, BOOSTER, grant agreement no. 862474, RoLA-FLEX, and grant agreement no. 101007084 CITYSOLAR, as well as EPSRC Projects EP/T026219/1 and EP/W017091/1.
The authors declare no competing interests.
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Quill, T.J., LeCroy, G., Halat, D.M. et al. An ordered, self-assembled nanocomposite with efficient electronic and ionic transport. Nat. Mater. 22, 362–368 (2023). https://doi.org/10.1038/s41563-023-01476-6