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Carrier multiplication between interacting nanocrystals for fostering silicon-based photovoltaics

Nature Photonics volume 6, pages 672–679 (2012)Cite this article

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Abstract

The conversion of solar radiation into electric current with high efficiency is one of the most important topics of modern scientific research, as it holds great potential as a source of clean and renewable energy. Exploitation of interaction between nanocrystals seems to be a promising route to the establishment of third-generation photovoltaics. Here, we adopt a fully ab initio scheme to estimate the role of nanoparticle interplay in the carrier multiplication dynamics of interacting silicon nanocrystals. Energy and charge transfer-based carrier multiplication events are studied as a function of nanocrystal separation, demonstrating the benefits induced by the wavefunction sharing regime. We prove the relevance of these recombinative mechanisms for photovoltaic applications in the case of silicon nanocrystals arranged in dense arrays, quantifying at an atomic scale which conditions maximize the outcome.

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Figure 1: Carrier multiplication lifetimes in non-interacting Si-NCs and Si bulk.
Figure 2: One- and two-site carrier multiplication.
Figure 3: Carrier multiplication lifetimes in interacting Si-NCs.
Figure 4: SSQC and CDCT lifetimes.
Figure 5: Role of wavefunction delocalization.
Figure 6: Wavefunction sharing regime.

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Acknowledgements

The authors thank the Super-Computing Interuniversity Consortium CINECA for support and high-performance computing resources under the Italian Super-Computing Resource Allocation (ISCRA) initiative, and the European Community's Seventh Framework Programme (FP7/2007-2013; grant agreement 245977). The authors thank G. Cantele and F. Iori for fruitful discussions.

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Authors and Affiliations

  1. Department of Physics, University of Modena and Reggio Emilia, via Campi 213/A, Modena, 41125, Italy

    Marco Govoni

  2. Department of Science and Methods for Engineering (DISMI), via Amendola 2 Pad. Morselli, Reggio Emilia, 42122, Italy

    Ivan Marri & Stefano Ossicini

  3. CNR-NANO Research Center S3, Via Campi 213/A, Modena, 41125, Italy

    Stefano Ossicini

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  1. Marco Govoni
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Contributions

M.G., I.M and S.O. conceived the project. M.G. and I.M. designed and performed simulations with a code developed by M.G., and co-wrote the manuscript. I.M. and S.O. supervised the project. All authors discussed the results and implications and commented on the manuscript at all stages.

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Correspondence to Marco Govoni or Ivan Marri.

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The authors declare no competing financial interests.

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Govoni, M., Marri, I. & Ossicini, S. Carrier multiplication between interacting nanocrystals for fostering silicon-based photovoltaics. Nature Photon 6, 672–679 (2012). https://doi.org/10.1038/nphoton.2012.206

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