Lattice contraction in free-standing CdSe nanocrystals
نویسندگان
چکیده
Colloidal CdSe nanocrystals ~NCs! with high photoluminescent quantum yield are fabricated by a method adopting a large initial Se:Cd ratio of the precursors in the solution. X-ray diffraction and Raman measurements confirm that there exists lattice contraction in the free-standing wurtzite CdSe NCs. The lattice contraction indicates the occurrence of surface optimization/reconstruction during the growth, which results in the high quantum yield of the obtained CdSe NCs. © 2002 American Institute of Physics. @DOI: 10.1063/1.1507613#
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