Gómez Daniel E, van Embden Joel, Mulvaney Paul, Fernée Mark J, Rubinsztein-Dunlop Halina
School of Chemistry and Bio21 Institute, The University of Melbourne, Parkville, VIC, 3010, Australia.
ACS Nano. 2009 Aug 25;3(8):2281-7. doi: 10.1021/nn900296q.
We report on the observation of an intermediate state in the blinking of single CdSe/CdS core-shell nanocrystals. This state has a low quantum yield and connects the "on" and "off" states commonly observed in the photoluminescence blinking of individual nanocrystals. We find that the transitions between these two emitting states follow nearly single-exponential statistics. The transitions from the "on" state to this intermediate state result from changes in the surface passivation of the nanocrystal. The data are consistent with photoinduced, adsorption/desorption events that take place at the surface of the nanocrystals. The trion state leads to a reduction in photoluminescence in nanocrystals.
我们报告了对单个CdSe/CdS核壳纳米晶体闪烁过程中一个中间态的观测结果。该状态具有较低的量子产率，并连接了单个纳米晶体光致发光闪烁中常见的“开”态和“关”态。我们发现这两种发射态之间的转变遵循近似单指数统计规律。从“开”态到这个中间态的转变是由纳米晶体表面钝化的变化引起的。这些数据与纳米晶体表面发生的光致吸附/解吸事件一致。三重态激子态会导致纳米晶体光致发光的降低。
