Dynamics of photogenerated holes in nanocrystalline α-Fe2O3 electrodes for water oxidation probed by transient absorption spectroscopy.

نویسندگان

  • Stephanie R Pendlebury
  • Monica Barroso
  • Alexander J Cowan
  • Kevin Sivula
  • Junwang Tang
  • Michael Grätzel
  • David Klug
  • James R Durrant
چکیده

Transient absorption spectroscopy on the μs-s time scale is used to monitor the yield and decay dynamics of photogenerated holes in nanocrystalline hematite photoanodes. In the absence of a positive applied bias, these holes are observed to undergo rapid electron-hole recombination. The application of a positive bias results in the generation of long-lived (3 ± 1 s lifetime) photoholes.

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عنوان ژورنال:
  • Chemical communications

دوره 47 2  شماره 

صفحات  -

تاریخ انتشار 2011