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Engineering charge transport by heterostructuring solution-processed semiconductors

Nature Reviews Materials volume 2, Article number: 17026 (2017) | Download Citation

Abstract

Solution-processed semiconductor devices are increasingly exploiting heterostructuring — an approach in which two or more materials with different energy landscapes are integrated into a composite system. Heterostructured materials offer an additional degree of freedom to control charge transport and recombination for more efficient optoelectronic devices. By exploiting energetic asymmetry, rationally engineered heterostructured materials can overcome weaknesses, augment strengths and introduce emergent physical phenomena that are otherwise inaccessible to single-material systems. These systems see benefit and application in two distinct branches of charge-carrier manipulation. First, they influence the balance between excitons and free charges to enhance electron extraction in solar cells and photodetectors. Second, they promote radiative recombination by spatially confining electrons and holes, which increases the quantum efficiency of light-emitting diodes. In this Review, we discuss advances in the design and composition of heterostructured materials, consider their implementation in semiconductor devices and examine unexplored paths for future advancement in the field.

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Author notes

    • Oleksandr Voznyy
    • , Brandon R. Sutherland
    •  & Alexander H. Ip

    These authors contributed equally to this work.

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  1. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.

    • Oleksandr Voznyy
    • , Brandon R. Sutherland
    • , Alexander H. Ip
    • , David Zhitomirsky
    •  & Edward H. Sargent

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The authors declare no competing interests.

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Correspondence to Edward H. Sargent.

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DOI

https://doi.org/10.1038/natrevmats.2017.26

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