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发光二极管

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[资源] 分享一篇牛人发在Nature上的文章：量子点发光淬灭机理的讨论

量子点的荧光猝灭机理一直难以得到一个完整的结论，这篇文章对量子点的荧光猝灭机理给出了详细的讨论与解释，希望对做量子点的虫子有帮助！！！
Photoluminescence blinking—random switching between states of high (ON) and low (OFF) emissivities—is a universal property of molecular emitters found in dyes1, polymers2, biological molecules3 and artificial nanostructures such as nanocrystal quantum dots, carbon nanotubes and nanowires4–6. For the past 15 years, colloidal nanocrystals have been used as a model system to study this phenomenon5,6. The occurrence of OFF periods in nanocrystal emission has been commonly attributed to the presence of an additional charge7, which leads to photoluminescence quenching by nonradiative recombination (the Auger mechanism)8. However, this ‘charging’ model was recently challenged in several reports9,10.Here we report time-resolved photoluminescence studies of
individual nanocrystal quantum dots performed while electrochemically controlling the degree of their charging, with the goal of clarifying the role of charging in blinking. We find that two distinct types of blinking are possible: conventional (A-type) blinking due to charging and discharging of the nanocrystal core, in which lower photoluminescence intensities correlate with shorter photoluminescence lifetimes; and a second sort (B-type), in which large changes in the emission intensity are not accompanied by significant changes in emission dynamics. We attribute B-type blinking to charge fluctuations in the electron-accepting surface
sites. When unoccupied, these sites intercept ‘hot’ electrons before they relax into emitting core states. Both blinking mechanisms can be electrochemically controlled and completely suppressed by application of an appropriate potential.

[ 来自科研家族梦家园 ][ Last edited by 发光二极管 on 2012-5-29 at 22:32 ]

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守望天空8633

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3楼: Originally posted by liuzhun168 at 2012-05-29 12:48:12
受限欢迎楼主上传文献，但楼主并没仔细看，或者看懂这篇文献，这篇很久以前就出来了，讨论的是量子点发光淬灭机理，一般之前的文献只讨论一种原因，而这篇文献给出了两种原因

O(∩_∩)O哈哈~，阁下好像也没有看清楚。这篇文章的做着是洛斯阿拉莫斯国家实验室的Vicotr的，讲的是量子点的闪烁现象（一种物理行为），和所谓的量子点猝灭机理是不同的。

你发文章分析之前，一定要分析清楚，自己都没有搞清楚，就在这里挂出来，纯粹是吸引眼球。

[ Last edited by 守望天空8633 on 2013-9-1 at 09:24 ]