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An ordered, self-assembled nanocomposite with efficient electronic and ionic transport

Nature Materials volume 22, pages 362–368 (2023)Cite this article

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Abstract

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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Fig. 1: Characterization of the nanocomposite structure.
Fig. 2: Structural evolution of the material under electrochemical charging.
Fig. 3: Operando organic electrochemical transistor transfer curve.
Fig. 4: Electrochemical charge modulation spectroscopy.

Data availability

All the data supporting the findings of this study are available within the Article, its Supplementary Information or from the corresponding authors upon request. Source data are provided with this paper.

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Acknowledgements

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.

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Authors and Affiliations

  1. Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA

    Tyler J. Quill, Garrett LeCroy, Adam Marks, Alexander Giovannitti & Alberto Salleo

  2. Department of Chemical and Biomolecular Engineering and College of Chemistry, University of California, Berkeley, CA, USA

    David M. Halat, Lorena S. Grundy, Jeffrey A. Reimer & Nitash P. Balsara

  3. Materials Sciences Division and Joint Center for Energy Storage Research, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

    David M. Halat, Lorena S. Grundy, Jeffrey A. Reimer & Nitash P. Balsara

  4. Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia

    Rajendar Sheelamanthula & Iain McCulloch

  5. Department of Chemistry, University of Oxford, Oxford, UK

    Iain McCulloch

  6. Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA

    Christopher J. Takacs

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  1. Tyler J. Quill
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Contributions

T.J.Q., C.J.T., A.S. and A.G. conceived the study. T.J.Q. and C.J.T. performed the operando X-ray scattering experiments and analysed the data. T.J.Q. and G.L. carried out the spectroscopic measurements and G.L. performed the exciton fitting. D.M.H. performed the PFG NMR measurements under the supervision of J.A.R. and N.P.B. R.S. synthesized p(g2T-TT) under the supervision of I.M. T.J.Q., A.G. and A.S. wrote the manuscript and all the authors contributed to manuscript preparation and editing.

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Correspondence to Alexander Giovannitti, Alberto Salleo or Christopher J. Takacs.

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Nature Materials thanks Magnus Berggren and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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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

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