Multiexciton solar cells of CuInSe2 nanocrystals

C. Jackson Stolle, Taylor B. Harvey, Douglas R. Pernik, Jarett I. Hibbert, Jiang Du, Dong Joon Rhee, Vahid A. Akhavan, Richard D. Schaller, Brian A. Korgel

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69 Citations (Scopus)

Abstract

Peak external quantum efficiencies (EQEs) of just over 120% were observed in photovoltaic (PV) devices of CuInSe2 nanocrystals prepared with a photonic curing process. The extraction of more than one electron/hole pair as a result of the absorption of a single photon can occur if multiple excitons are generated and extracted. Multiexciton generation (MEG) in the nanocrystal films was substantiated by transient absorption spectroscopy. We propose that photonic curing leads to sufficient electronic coupling between nanocrystals to enable multiexciton extraction under typical solar illumination conditions. Under low light conditions, however, the EQE drops significantly, indicating that photonic curing-induced ligand desorption creates a significant amount of traps in the film that limit the overall power conversion efficiency of the device.

Original languageEnglish
Pages (from-to)304-309
Number of pages6
JournalJournal of Physical Chemistry Letters
Volume5
Issue number2
DOIs
Publication statusPublished - Jan 16 2014

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Keywords

  • CIGS
  • multiple excitons
  • nanocrystals
  • photonic curing
  • photovoltaics
  • solar cells

ASJC Scopus subject areas

  • Materials Science(all)
  • Physical and Theoretical Chemistry

Cite this

Stolle, C. J., Harvey, T. B., Pernik, D. R., Hibbert, J. I., Du, J., Rhee, D. J., Akhavan, V. A., Schaller, R. D., & Korgel, B. A. (2014). Multiexciton solar cells of CuInSe2 nanocrystals. Journal of Physical Chemistry Letters, 5(2), 304-309. https://doi.org/10.1021/jz402596v