Photoluminescence dynamics of energy transfer between CdS quantum dots prepared by a colloidal method
Photoluminescence dynamics of energy transfer between CdS quantum dots prepared by a colloidal method
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DOI：
10.1016/j.jlumin.2006.01.209
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发表时间：
2007
影响因子：
3.6
通讯作者：
K. Tomihira;Daegwi Kim;M. Nakayama
中科院分区：
文献类型：
--
作者：
K. Tomihira;Daegwi Kim;M. Nakayama
研究了胶体法制备的CdS量子点中的能量传递过程。通过应用表面改性方法，带边光致发光（PL）被强烈地观察为主PL带。将表面改性的QD分散在聚乙烯醇膜中，其中QD溶液以1至250的倍数不同地浓缩。集中度的变化对应于QD之间的平均距离的变化。在1，10，和75倍浓缩的样品中，带边PL的衰减曲线不依赖于检测能量，并表现出数百纳秒的顺序缓慢衰减。另一方面，PL-衰减曲线在250倍浓缩样品表现出更快的衰减相比，稀释样品。由于CdS量子点之间有效的能量转移过程，更快的衰减表明一个新的衰减通道。
We have investigated the energy transfer process in CdS quantum dots (QDs) prepared by a colloidal method. By applying a surface-modification method, the band-edge photoluminescence (PL) is intensely observed as a main PL band. The surface-modified QDs were dispersed in polyvinyl alcohol films, where the QD solutions were variously concentrated by a factor from 1 to 250. The change of the degree of concentration corresponds to the change of a mean distance between QDs. In the 1-, 10-, and 75-times concentrated samples, the decay profiles of the band-edge PL do not depend on detection energies and exhibit a slow decay in the order of hundreds of nanosecond. On the other hand, the PL-decay profiles in the 250-times concentrated sample exhibit faster decays as compared with the dilute samples. The faster decay suggests a new decay channel due to an effective energy transfer process between CdS QDs.