Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

2D coherent charge transport in highly ordered conducting polymers doped by solid state diffusion

Nature Materials volume 15, pages 896–902 (2016)Cite this article

Subjects

Abstract

Doping is one of the most important methods to control charge carrier concentration in semiconductors. Ideally, the introduction of dopants should not perturb the ordered microstructure of the semiconducting host. In some systems, such as modulation-doped inorganic semiconductors or molecular charge transfer crystals, this can be achieved by spatially separating the dopants from the charge transport pathways. However, in conducting polymers, dopants tend to be randomly distributed within the conjugated polymer, and as a result the transport properties are strongly affected by the resulting structural and electronic disorder. Here, we show that in the highly ordered lamellar microstructure of a regioregular thiophene-based conjugated polymer, a small-molecule p-type dopant can be incorporated by solid state diffusion into the layers of solubilizing side chains without disrupting the conjugated layers. In contrast to more disordered systems, this allows us to observe coherent, free-electron-like charge transport properties, including a nearly ideal Hall effect in a wide temperature range, a positive magnetoconductance due to weak localization and the Pauli paramagnetic spin susceptibility.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Get just this article for as long as you need it

$39.95

Learn more

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Highly ordered microstructure of doped PBTTT/F4-TCNQ.
Figure 2: Delocalized charge transport in doped PBTTT/F4-TCNQ.
Figure 3: Weak localization in the magnetoconductance of doped PBTTT/F4-TCNQ.
Figure 4: Comparison with the transport properties of disordered PEDOT:PSS.

References

  1. Yu, G., Gao, J., Hummelen, J., Wudl, F. & Heeger, A. Polymer photovoltaic cells: enhanced efficiencies via a network of internal donor–acceptor heterojunctions. Science 270, 1789–1791 (1995).

    Article  CAS  Google Scholar 

  2. Meijer, E. et al. Solution-processed ambipolar organic field-effect transistors and inverters. Nature Mater. 2, 678–682 (2003).

    Article  CAS  Google Scholar 

  3. Alves, H., Molinari, A. S., Xie, H. & Morpurgo, A. F. Metallic conduction at organic charge-transfer interfaces. Nature Mater. 7, 574–580 (2008).

    Article  CAS  Google Scholar 

  4. Gutiérrez Lezama, I. et al. Single-crystal organic charge-transfer interfaces probed using Schottky-gated heterostructures. Nature Mater. 11, 788–794 (2012).

    Article  Google Scholar 

  5. Chiang, C. K. et al. Electrical conductivity in doped polyacetylene. Phys. Rev. Lett. 39, 1098–1101 (1977).

    Article  CAS  Google Scholar 

  6. Bryce, M. R. Recent progress on conducting organic charge-transfer salts. Chem. Soc. Rev. 20, 355–390 (1991).

    Article  CAS  Google Scholar 

  7. Friend, R. Conductive Polymers II: From Science to Applications Vol. 2 (RAPRA review reports, Rapra Technology, 1993).

    Google Scholar 

  8. Inzelt, G. Conducting Polymers 245–293 (Springer, 2012).

    Book  Google Scholar 

  9. Kiebooms, R., Aleshin, A., Hutchison, K. & Wudl, F. Thermal and electromagnetic behavior of doped poly(3,4-ethylenedioxythiophene) films. J. Phys. Chem. B 101, 11037–11039 (1997).

    Article  CAS  Google Scholar 

  10. Lee, K. et al. Metallic transport in polyaniline. Nature 441, 65–68 (2006).

    Article  CAS  Google Scholar 

  11. Bubnova, O. et al. Semi-metallic polymers. Nature Mater. 13, 190–194 (2014).

    Article  CAS  Google Scholar 

  12. Chang, Y., Lee, K., Kiebooms, R., Aleshin, A. & Heeger, A. J. Reflectance of conducting poly(3,4-ethylenedioxythiophene). Synth. Met. 105, 203–206 (1999).

    Article  CAS  Google Scholar 

  13. Ikehata, S. et al. Solitons in polyacetylene: magnetic susceptibility. Phys. Rev. Lett. 45, 1123–1126 (1980).

    Article  CAS  Google Scholar 

  14. Podzorov, V., Menard, E., Rogers, J. & Gershenson, M. Hall effect in the accumulation layers on the surface of organic semiconductors. Phys. Rev. Lett. 95, 226601 (2005).

    Article  CAS  Google Scholar 

  15. Chang, J.-F. et al. Hall-effect measurements probing the degree of charge-carrier delocalization in solution-processed crystalline molecular semiconductors. Phys. Rev. Lett. 107, 066601 (2011).

    Article  Google Scholar 

  16. Uemura, T. et al. Temperature dependence of the Hall effect in pentacene field-effect transistors: possibility of charge decoherence induced by molecular fluctuations. Phys. Rev. B 85, 035313 (2012).

    Article  Google Scholar 

  17. Wang, S., Ha, M., Manno, M., Daniel Frisbie, C. & Leighton, C. Hopping transport and the Hall effect near the insulator-metal transition in electrochemically gated poly(3-hexylthiophene) transistors. Nature Commun. 3, 1210 (2012).

    Article  Google Scholar 

  18. Lee, B. et al. Trap healing and ultralow-noise Hall effect at the surface of organic semiconductors. Nature Mater. 12, 1125–1129 (2013).

    Article  CAS  Google Scholar 

  19. Yamashita, Y. et al. Transition between band and Hopping transport in polymer field-effect transistors. Adv. Mater. 26, 8169–8173 (2014).

    Article  CAS  Google Scholar 

  20. Senanayak, S. P., Ashar, A. Z., Kanimozhi, C., Patil, S. & Narayan, K. S. Room-temperature bandlike transport and Hall effect in a high-mobility ambipolar polymer. Phys. Rev. B 91, 115302 (2015).

    Article  Google Scholar 

  21. Friedman, L. Hall conductivity of amorphous semiconductors in the random phase model. J. Non-Cryst. Solids 6, 329–341 (1971).

    Article  CAS  Google Scholar 

  22. Klein, R. S. Investigation of the Hall effect in impurity-hopping conduction. Phys. Rev. B 31, 2014–2021 (1985).

    Article  CAS  Google Scholar 

  23. Seeger, K., Gill, W., Clarke, T. & Street, G. Conductivity and Hall effect measurements in doped polyacetylene. Solid State Commun. 28, 873–878 (1978).

    Article  CAS  Google Scholar 

  24. Shacklette, L. W., Chance, R. R., Ivory, D. M., Miller, G. G. & Baughman, R. H. Electrical and optical properties of highly conducting charge-transfer complexes of poly (p-phenylene). Synth. Met. 1, 307–320 (1980).

    Article  CAS  Google Scholar 

  25. MacDiarmid, A. G. & Chiang, J. C. Polyanline: protonic acid doping of the emeraldine form to the metallic regime. Synth. Met. 13, 193–205 (1986).

    Article  Google Scholar 

  26. Aziz, E. F. et al. Localized charge transfer in a molecularly doped conducting polymer. Adv. Mater. 19, 3257–3260 (2007).

    Article  CAS  Google Scholar 

  27. Zhang, Y., de Boer, B. & Blom, P. W. M. Controllable molecular doping and charge transport in solution-processed polymer semiconducting layers. Adv. Funct. Mater. 19, 1901–1905 (2009).

    Article  CAS  Google Scholar 

  28. Cochran, J. E. et al. Molecular interactions and ordering in electrically doped polymers: blends of PBTTT and F4TCNQ. Macromolecules 47, 6836–6846 (2014).

    Article  CAS  Google Scholar 

  29. Heeger, A. J., Kivelson, S., Schrieffer, J. R. & Su, W. P. Solitons in conducting polymers. Rev. Mod. Phys. 60, 781–850 (1988).

    Article  CAS  Google Scholar 

  30. Kline, R. J. et al. Critical role of side-chain attachment density on the order and device performance of polythiophenes. Macromolecules 40, 7960–7965 (2007).

    Article  CAS  Google Scholar 

  31. Tanaka, H., Hirate, M., Watanabe, S. & Kuroda, S.-I. Microscopic signature of metallic state in semicrystalline conjugated polymers doped with fluoroalkylsilane molecules. Adv. Mater. 26, 2376–2383 (2014).

    Article  CAS  Google Scholar 

  32. Dingle, R., Störmer, H. L., Gossard, A. C. & Wiegmann, W. Electron mobilities in modulation-doped semiconductor heterojunction superlattices. Appl. Phys. Lett. 33, 665–667 (1978).

    Article  CAS  Google Scholar 

  33. Mizoguchi, K. et al. Pauli and curie susceptibilities of polythiophene. Synth. Met. 18, 195–198 (1987).

    Article  CAS  Google Scholar 

  34. Efros, A. L. & Shklovskii, B. I. Coulomb gap and low temperature conductivity of disordered systems. J. Phys. C: Solid State Phys. 8, 49–51 (1975).

    Article  Google Scholar 

  35. Orton, J. & Powell, M. The Hall effect in polycrystalline and powdered semiconductors. Rep. Progress Phys. 43, 1263–1307 (1980).

    Article  Google Scholar 

  36. Holstein, T. Hall effect in impurity conduction. Phys. Rev. 124, 1329–1347 (1961).

    Article  Google Scholar 

  37. Le Comber, P. G., Jones, D. I. & Spear, W. E. Hall effect and impurity conduction in substitutionally doped amorphous silicon. Philos. Mag. 35, 1173–1187 (1977).

    Article  CAS  Google Scholar 

  38. Gilani, T. H., Masui, T., Logvenov, G. Yu. & Ishiguro, T. Low-temperature Hall effect and thermoelectric power in metallic PF6-doped polypyrrole. Synth. Met. 78, 327–331 (1996).

    Article  CAS  Google Scholar 

  39. Long, V. C., Washburn, S., Chen, X. L. & Jenekhe, S. A. Hall-effect study of an ion-bombarded polymer. J. Appl. Phys. 80, 4202–4204 (1996).

    Article  CAS  Google Scholar 

  40. McCulloch, I. et al. Liquid-crystalline semiconducting polymers with high charge-carrier mobility. Nature Mater. 5, 328–333 (2006).

    Article  CAS  Google Scholar 

  41. Mityashin, A. et al. Unraveling the mechanism of molecular doping in organic semiconductors. Adv. Mater. 24, 1535–1539 (2012).

    Article  CAS  Google Scholar 

  42. Lee, P. A. & Ramakrishnan, T. Disordered electronic systems. Rev. Mod. Phys. 57, 287–337 (1985).

    Article  CAS  Google Scholar 

  43. Ahlskog, M., Reghu, M., Heeger, A., Noguchi, T. & Ohnishi, T. Electronic transport in the metallic state of oriented poly(p-phenylenevinylene). Phys. Rev. B 53, 15529–15537 (1996).

    Article  CAS  Google Scholar 

  44. Väkiparta, K. et al. Anisotropy of magnetoconductivity in oriented poly(acetylene) doped with iodine. Synth. Met. 57, 4860–4865 (1993).

    Article  Google Scholar 

  45. Aleshin, A. N., Kozub, V. I., Suh, D. S. & Park, Y. W. Saturation of dephasing and magnetoresistance features in heavily doped polyacetylene. Synth. Met. 135–136, 303–304 (2003).

    Article  Google Scholar 

  46. Mukherjee, A. K. & Menon, R. Magnetotransport in doped polyaniline. J. Phys. Condens. Matter 17, 1947–1960 (2005).

    Article  CAS  Google Scholar 

  47. Zanettini, S. et al. Magnetoconductance anisotropy of a polymer thin film at the onset of metallicity. Appl. Phys. Lett. 106, 063303 (2015).

    Article  Google Scholar 

  48. Hikami, S., Larkin, A. & Nagaoka, Y. Spin–orbit interaction and magnetoresistance in the two-dimensional random system. Prog. Theor. Phys. 63, 707–710 (1980).

    Article  Google Scholar 

Download references

Acknowledgements

The research leading to these results has received funding from an ERC Synergy Grant SC2 (No. 610115) supported by the European Research Council. K.K. thanks the Samsung Scholarship Foundation for financial support. S.W. thanks H. Matsui and J. Takeya of University of Tokyo for stimulating discussions, and is supported by Research Fellowships of Japan Society for the Promotion of Science for Young Scientists, and JST PRESTO. K.B. acknowledges funding by the German Research Foundation (BR 4869/1-1). S.-i.K. and H.T. acknowledge funding from the Japan Society for the Promotion of Science (No. 25287073). The authors thank D. Venkateshvaran and A. Sadhanala of the University of Cambridge for help with the measurements. Part of this work is based on research conducted at the Cornell High Energy Synchrotron Source (CHESS). CHESS is supported by the NSF & NIH/NIGMS via NSF award DMR-1332208. We thank D.-M. Smilgies, X. Sheng and J. Dolan for their help during the D1 experiment at CHESS. We thank A. Hexemer, R. Pandolfi and C. Zhu for supporting the data evaluation, who are supported by the US Department of Energy under Contract No. DE-AC02-05CH1123, the ECA award Program and the LBNL LDRD “TReXS”. The authors thank Professor Klaus Müllen of Max Planck Institute for Polymer Research for providing CDT-BTZ.

Author information

Author notes

  1. Keehoon Kang and Shun Watanabe: These authors contributed equally to this work.

Authors and Affiliations

  1. Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, UK

    Keehoon Kang, Shun Watanabe, Katharina Broch, Adam Brown, Iyad Nasrallah, Mark Nikolka & Henning Sirringhaus

  2. Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8561, Chiba, Japan

    Shun Watanabe

  3. JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan

    Shun Watanabe

  4. Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland

    Alessandro Sepe

  5. Department of Chemistry and Centre for Plastic Electronics, Imperial College, London SW7 2AZ, UK

    Zhuping Fei & Martin Heeney

  6. Division of Materials Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan

    Daisuke Matsumoto & Kazuhiro Marumoto

  7. Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan

    Kazuhiro Marumoto

  8. Department of Applied Physics, Nagoya University, Chikusa, Nagoya 464-8603, Japan

    Hisaaki Tanaka & Shin-ichi Kuroda

Authors
  1. Keehoon Kang
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Shun Watanabe
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Katharina Broch
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Alessandro Sepe
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Adam Brown
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Iyad Nasrallah
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Mark Nikolka
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Zhuping Fei
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Martin Heeney
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Daisuke Matsumoto
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Kazuhiro Marumoto
    View author publications

    You can also search for this author in PubMed Google Scholar

  12. Hisaaki Tanaka
    View author publications

    You can also search for this author in PubMed Google Scholar

  13. Shin-ichi Kuroda
    View author publications

    You can also search for this author in PubMed Google Scholar

  14. Henning Sirringhaus
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

K.K. and S.W. conceived, designed, performed the experiments, fabricated all the samples, analysed the data and wrote the manuscript with significant input from H.S. All X-ray measurements were done by K.B. and A.S. A.B. performed XPS measurements. I.N. measured the temperature-dependent UV–Vis optical absorption spectrum of PBTTT/F4-TCNQ and M.N. performed FTIR measurements (Supplementary information). ESR measurements were performed by H.T. and S.-i.K. (for PBTTT/F4-TCNQ), and by D.M. and K.M. (for PEDOT/PSS). Z.F. and M.H. synthesized and purified the PBTTT. S.W. and H.S. supervised this work. All authors discussed the results and reviewed the manuscript.

Corresponding author

Correspondence to Henning Sirringhaus.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 5460 kb)

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kang, K., Watanabe, S., Broch, K. et al. 2D coherent charge transport in highly ordered conducting polymers doped by solid state diffusion. Nature Mater 15, 896–902 (2016). https://doi.org/10.1038/nmat4634

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmat4634

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing