Redox Brightening of Colloidal Semiconductor Nanocrystals Using Molecular Reductants
Redox Brightening of Colloidal Semiconductor Nanocrystals Using Molecular Reductants
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DOI：
10.1021/ja307996b
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发表时间：
2012-10-03
影响因子：
15
通讯作者：
Gamelin, Daniel R.
中科院分区：
文献类型：
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作者：
Rinehart, Jeffrey D.;Weaver, Amanda L.;Gamelin, Daniel R.
亚导带电势的化学还原剂可以在胶体ZnSe基纳米晶中诱导出较大的光致发光增强。通过添加外球还原剂，胶体Mn2+掺杂ZnSe纳米晶的光致发光量子产率从14%提高到80%。对于起始量子产率较低的纳米晶体，观察到高达48倍的氧化还原发光。一旦暴露在空气中，这些增加很快就会逆转，即使在厌氧条件下也是暂时的。这种氧化还原发光过程为理解氧化还原活性表面“陷阱态”及其对胶体半导体纳米晶物理性质的贡献提供了一种新的、系统的方法。
Chemical reductants of sub-conduction-band potentials are demonstrated to induce large photoluminescence enhancement in colloidal ZnSe-based nanocrystals. The photoluminescence quantum yield of colloidal Mn2+-doped ZnSe nanocrystals has been improved from 14% to 80% simply by addition of an outer-sphere reductant. Up to 48-fold redox brightening is observed for nanocrystals with lower starting quantum yields. These increases are quickly reversed upon exposure to air and are temporary even under anaerobic conditions. This redox brightening process offers a new and systematic approach to understanding redox-active surface "trap states" and their contributions to the physical properties of colloidal semiconductor nanocrystals.