Temperature and Excitation Wavelength Dependence of Surface-Plasmon-Mediated Emission from CdSe Nanocrystals
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- 作者：Liu Lu ; Daifen Chen ; Guangming Zhao ; Xifeng Ren ; Guangcan Guo
- 刊名：Journal of Physical Chemistry C
- 出版年：2010
- 出版时间：November 4, 2010
- 年：2010
- 卷：114
- 期：43
- 页码：18435-18438
- 全文大小：240K
- 年卷期：v.114,no.43(November 4, 2010)
- ISSN：1932-7455
文摘
The authors demonstrate the temperature-dependent behavior of surface plasmon (SP) coupling emission of CdSe nanocrystals (NCs) on Au colloids at different excitation wavelengths. It is found that the photoluminescence (PL) enhancement factor of CdSe NCs on Au colloids increases with the measuring temperature from 8 to 300 K. Such a trend is independent of the excitation wavelength, which whereas greatly influences the PL enhancement factor and the critical temperature for PL quenching switching to enhancement. We attribute the temperature-dependent PL enhancement factor to the increase of the SP coupling rate kSP and the red shift of the PL energy of CdSe NCs with the rising temperature. Both the PL intensity and the energy of CdSe nanocrystals are modeled against the temperature (7−300 K). Compared with the bare nanocrystals, the nanocrystals on Au colloids have an equal activation energy, a larger temperature coefficient, and a temperature-dependent red shift of the PL energy.