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Solar-energy conversion and light emission in an atomic monolayer p–n diode

Nature Nanotechnology volume 9, pages 257–261 (2014)Cite this article

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Abstract

The limitations of the bulk semiconductors currently used in electronic devices—rigidity, heavy weight and high costs—have recently shifted the research efforts to two-dimensional atomic crystals1 such as graphene2 and atomically thin transition-metal dichalcogenides3,4. These materials have the potential to be produced at low cost and in large areas, while maintaining high material quality. These properties, as well as their flexibility, make two-dimensional atomic crystals attractive for applications such as solar cells or display panels. The basic building blocks of optoelectronic devices are p–n junction diodes, but they have not yet been demonstrated in a two-dimensional material. Here, we report a p–n junction diode based on an electrostatically doped5 tungsten diselenide (WSe2) monolayer. We present applications as a photovoltaic solar cell, a photodiode and a light-emitting diode, and obtain light–power conversion and electroluminescence efficiencies of ∼0.5% and ∼0.1%, respectively. Given recent advances in the large-scale production of two-dimensional crystals6,7, we expect them to profoundly impact future developments in solar, lighting and display technologies.

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Figure 1: WSe2 monolayer device with split gate electrodes.
Figure 2: Electrical characterization.
Figure 3: Device operation as solar cell and photodiode.
Figure 4: Device operation as light-emitting diode.

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Acknowledgements

The authors thank K. Unterrainer for encouragement, M. Brandstetter, M. Krall and W. Schrenk for technical assistance and E. Bertagnolli for providing access to a Raman spectrometer. The research leading to these results has received funding from the Austrian Science Fund FWF (START Y-539) and the European Union Seventh Framework Programme (grant agreement no. 604391 Graphene Flagship).

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Authors and Affiliations

  1. Vienna University of Technology, Institute of Photonics, Gußhausstraße 27-29, 1040, Vienna, Austria

    Andreas Pospischil, Marco M. Furchi & Thomas Mueller

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  1. Andreas Pospischil
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  2. Marco M. Furchi
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Contributions

T.M. conceived the experiment. A.P. fabricated the devices and carried out the measurements. M.F. contributed to sample fabrication. A.P. and M.F. built the experimental set-ups. A.P. and T.M. analysed the data. T.M. prepared the manuscript. All authors discussed the results and commented on the manuscript.

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Correspondence to Thomas Mueller.

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The authors declare no competing financial interests.

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Pospischil, A., Furchi, M. & Mueller, T. Solar-energy conversion and light emission in an atomic monolayer p–n diode. Nature Nanotech 9, 257–261 (2014). https://doi.org/10.1038/nnano.2014.14

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