High efficiency photoluminescence from silica-coated CdSe quantum dots

Qian, Lei; Bera, Debasis; Tseng, Teng-Kuan; Holloway, Paul. H.
February 2009
Applied Physics Letters;2/16/2009, Vol. 94 Issue 7, pN.PAG
Academic Journal
The effects on the luminescent properties of coating CdSe quantum dots with silica are presented. Coating increased the quantum yields from ∼10%–20% to ∼80% at a maximum. The changes in quantum yields and photoluminescence peak at wavelength were discussed in terms of the effects of surface charge. By neutralizing surface charge, the emission from CdSe quantum dots was initially blueshifted followed by redshifting, and the quantum yield increased dramatically.


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