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.

  • Article
  • Published:

Vertical and in-plane heterostructures from WS2/MoS2 monolayers

Abstract

Layer-by-layer stacking or lateral interfacing of atomic monolayers has opened up unprecedented opportunities to engineer two-dimensional heteromaterials. Fabrication of such artificial heterostructures with atomically clean and sharp interfaces, however, is challenging. Here, we report a one-step growth strategy for the creation of high-quality vertically stacked as well as in-plane interconnected heterostructures of WS2/MoS2 via control of the growth temperature. Vertically stacked bilayers with WS2 epitaxially grown on top of the MoS2 monolayer are formed with preferred stacking order at high temperature. A strong interlayer excitonic transition is observed due to the type II band alignment and to the clean interface of these bilayers. Vapour growth at low temperature, on the other hand, leads to lateral epitaxy of WS2 on MoS2 edges, creating seamless and atomically sharp in-plane heterostructures that generate strong localized photoluminescence enhancement and intrinsic p–n junctions. The fabrication of heterostructures from monolayers, using simple and scalable growth, paves the way for the creation of unprecedented two-dimensional materials with exciting properties.

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

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

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

Figure 1: Schematic of the synthesis and the overall morphologies of the vertically stacked and in-plane WS2/MoS2 heterostructures.
Figure 2: STEM Z-contrast imaging and elemental mapping of the stacked WS2/MoS2 heterostructures.
Figure 3: Raman and PL characterization of the WS2/MoS2 vertical heterostructure.
Figure 4: Atomic structure of the lateral heterojunctions between WS2 and MoS2 monolayers.
Figure 5: Raman and PL characterizations of in-plane WS2/MoS2 heterojunction.

Similar content being viewed by others

References

  1. Kroemer, H. Heterostructure bipolar transistors and integrated circuits. Proc. IEEE 70, 13–25 (1982).

    Article  Google Scholar 

  2. Ohno, Y. et al. Electrical spin injection in a ferromagnetic semiconductor heterostructure. Nature 402, 790–792 (1999).

    Article  CAS  Google Scholar 

  3. Novoselov, K. S. et al. Two-dimensional gas of massless Dirac fermions in graphene. Nature 438, 197–200 (2005).

    Article  CAS  Google Scholar 

  4. Dean, C. R. et al. Boron nitride substrates for high-quality graphene electronics. Nature Nanotech. 5, 722–726 (2010).

    Article  CAS  Google Scholar 

  5. Song, L. et al. Large scale growth and characterization of atomic hexagonal boron nitride layers. Nano Lett. 10, 3209–3215 (2010).

    Article  CAS  Google Scholar 

  6. Gutierrez, H. R. et al. Extraordinary room-temperature photoluminescence in triangular WS2 monolayers. Nano Lett. 13, 3447–3454 (2013).

    Article  CAS  Google Scholar 

  7. Mak, K. F., Lee, C., Hone, J., Shan, J. & Heinz, T. F. Atomically thin MoS2: A new direct-gap semiconductor. Phys. Rev. Lett. 105, 136805 (2010).

    Article  Google Scholar 

  8. Najmaei, S. et al. Vapour phase growth and grain boundary structure of molybdenum disulphide atomic layers. Nature Mater. 12, 754–759 (2013).

    Article  CAS  Google Scholar 

  9. van der Zande, A. M. et al. Grains and grain boundaries in highly crystalline monolayer molybdenum disulphide. Nature Mater. 12, 554–561 (2013).

    Article  CAS  Google Scholar 

  10. Britnell, L. et al. Field-effect tunneling transistor based on vertical graphene heterostructures. Science 335, 947–950 (2012).

    Article  CAS  Google Scholar 

  11. Gannett, W. et al. Boron nitride substrates for high mobility chemical vapor deposited graphene. Appl. Phys. Lett. 98, 242105 (2011).

    Article  Google Scholar 

  12. Geim, A. K. & Grigorieva, I. V. Van der Waals heterostructures. Nature 499, 419–425 (2013).

    Article  CAS  Google Scholar 

  13. Georgiou, T. et al. Vertical field-effect transistor based on graphene-WS2 heterostructures for flexible and transparent electronics. Nature Nanotech. 8, 100–103 (2013).

    Article  CAS  Google Scholar 

  14. Yu, W. J. et al. Highly efficient gate-tunable photocurrent generation in vertical heterostructures of layered materials. Nature Nanotech. 8, 952–958 (2013).

    Article  CAS  Google Scholar 

  15. Pospischil, A., Furchi, M. M. & Mueller, T. Solar-energy conversion and light emission in an atomic monolayer p–n diode. Nature Nanotech. 9, 257–261 (2014).

    Article  CAS  Google Scholar 

  16. Baugher, B. W., Churchill, H. O., Yang, Y. & Jarillo-Herrero, P. Optoelectronic devices based on electrically tunable p–n diodes in a monolayer dichalcogenide. Nature Nanotech. 9, 262–267 (2014).

    Article  CAS  Google Scholar 

  17. Ross, J. S. et al. Electrically tunable excitonic light-emitting diodes based on monolayer WSe2 p–n junctions. Nature Nanotech. 9, 268–272 (2014).

    Article  CAS  Google Scholar 

  18. Haigh, S. J. et al. Cross-sectional imaging of individual layers and buried interfaces of graphene-based heterostructures and superlattices. Nature Mater. 11, 764–767 (2012).

    Article  CAS  Google Scholar 

  19. Yang, W. et al. Epitaxial growth of single-domain graphene on hexagonal boron nitride. Nature Mater. 12, 792–797 (2013).

    Article  CAS  Google Scholar 

  20. Levendorf, M. P. et al. Graphene and boron nitride lateral heterostructures for atomically thin circuitry. Nature 488, 627–632 (2012).

    Article  CAS  Google Scholar 

  21. Liu, Z. et al. In-plane heterostructures of graphene and hexagonal boron nitride with controlled domain sizes. Nature Nanotech. 8, 119–124 (2013).

    Article  CAS  Google Scholar 

  22. Liu, L. et al. Heteroepitaxial growth of two-dimensional hexagonal boron nitride templated by graphene edges. Science 343, 163–167 (2014).

    Article  CAS  Google Scholar 

  23. Han, G. H. et al. Continuous growth of hexagonal graphene and boron nitride in-plane heterostructures by atmospheric pressure chemical vapor deposition. ACS Nano 7, 10129–10138 (2013).

    Article  CAS  Google Scholar 

  24. Miyata, Y. et al. Fabrication and characterization of graphene/hexagonal boron nitride hybrid sheets. Appl. Phys. Express 5, 085102 (2012).

    Article  Google Scholar 

  25. Kosmider, K. & Fernandez-Rossier, J. Electronic properties of the MoS2–WS2 heterojunction. Phys. Rev. B 87, 075451 (2013).

    Article  Google Scholar 

  26. Terrones, H., Lopez-Urias, F. & Terrones, M. Novel hetero-layered materials with tunable direct band gaps by sandwiching different metal disulfides and diselenides. Sci. Rep. 3, 1549 (2013).

    Article  Google Scholar 

  27. Kang, J., Tongay, S., Zhou, J., Li, J. B. & Wu, J. Q. Band offsets and heterostructures of two-dimensional semiconductors. Appl. Phys. Lett. 102, 012111 (2013).

    Article  Google Scholar 

  28. Krivanek, O. L. et al. Atom-by-atom structural and chemical analysis by annular dark-field electron microscopy. Nature 464, 571–574 (2010).

    Article  CAS  Google Scholar 

  29. Zhou, W. et al. Intrinsic structural defects in monolayer molybdenum disulfide. Nano Lett. 13, 2615–2622 (2013).

    Article  CAS  Google Scholar 

  30. Gong, Y. J. et al. Band gap engineering and layer-by-layer mapping of selenium-doped molybdenum disulfide. Nano Lett. 14, 442–449 (2014).

    Article  CAS  Google Scholar 

  31. Terrones, H. et al. New first order Raman-active modes in few layered transition metal dichalcogenides. Sci. Rep. 4, 4215 (2014).

    Article  CAS  Google Scholar 

  32. Berkdemir, A. et al. Identification of individual and few layers of WS2 using Raman spectroscopy. Sci. Rep. 3, 1755 (2013).

    Article  Google Scholar 

  33. Zhao, W. J. et al. Evolution of electronic structure in atomically thin sheets of WS2 and WSe2 . ACS Nano 7, 791–797 (2013).

    Article  CAS  Google Scholar 

  34. Peimyoo, N. et al. Nonblinking, intense two-dimensional light emitter: Monolayer WS2 triangles. ACS Nano 7, 10985–10994 (2013).

    Article  CAS  Google Scholar 

  35. Wang, Z. et al. Mixed low-dimensional nanomaterial: 2D ultranarrow MoS2 inorganic nanoribbons encapsulated in quasi-1D carbon nanotubes. J. Am. Chem. Soc. 132, 13840–13847 (2010).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank A. Lupini for providing the script for STEM image quantification. This work was supported by the Army Research Office MURI grant W911NF-11-1-0362, US DOE grant DE-FG02-09ER46554 (J.L., S.T.P.), a Wigner Fellowship through the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory (ORNL), managed by UT-Battelle, LLC, for the US DOE (W.Z.), the FAME Center, one of six centres of STARnet, a Semiconductor Research Corporation program sponsored by MARCO and DARPA, the US Office of Naval Research MURI grant N000014-09-1-1066, NSF grant ECCS-1327093 and MOE Academic Research Fund (AcRF) Tier 1 RG81/12 project Singapore and Si-COE project, Singapore. This research was also supported through a user project supported by ORNL’s Center for Nanophase Materials Sciences (CNMS), which is sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, US DOE. This research used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231. This work was also supported by the Singapore National Research Foundation under NRF RF Award No. NRF-RF2013-08, the start-up funding from Nanyang Technological University (M4081137.070).

Author information

Authors and Affiliations

Authors

Contributions

Y.G., J.L. and X.W. contributed equally to this work. Y.G. designed the growth procedures and carried out part of the characterization. Y.G., X.W. and G.Y. worked on the growth. W.Z. and J.L. carried out STEM experiments. G.S. and S.L. made the FET devices and carried out the electrical measurement. Z.L. performed part of the Raman and PL characterization. H.T., X.Z. and J.L. carried out DFT calculations. Y.G., J.L., X.W., W.Z., Z.L., G.S., S.L., M.T., H.T. and P.M.A. analysed the results and co-wrote the paper. All authors participated in discussions.

Corresponding authors

Correspondence to Wu Zhou or Pulickel M. Ajayan.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 1968 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Gong, Y., Lin, J., Wang, X. et al. Vertical and in-plane heterostructures from WS2/MoS2 monolayers. Nature Mater 13, 1135–1142 (2014). https://doi.org/10.1038/nmat4091

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmat4091

This article is cited by

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