Surface transformation and photoinduced recovery in CdSe nanocrystals.

نویسندگان

  • B C Hess
  • I G Okhrimenko
  • R C Davis
  • B C Stevens
  • Q A Schulzke
  • K C Wright
  • C D Bass
  • C D Evans
  • S L Summers
چکیده

CdSe nanocrystals in solution and films can enter a metastable state in which the highly luminescent nanocrystals become dark. This change, which we attribute to a surface transformation, can be caused by heating or by changing the environment of the nanocrystals at room temperature. The metastable transformation is reversed upon illumination of above-band-gap light, at which point the nanocrystals are again highly luminescent.

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عنوان ژورنال:
  • Physical review letters

دوره 86 14  شماره 

صفحات  -

تاریخ انتشار 2001