Photo-oxidation-enhanced coupling in densely packed CdSe quantum-dot films

Photo-oxidation of densely packed monolayer of CdSe quantum dots (QDs) was studied by time-resolved photoluminescence (PL) spectroscopy. Electrons yielded in QDs by the strong laser-pulse irradiation can assist the oxidation of CdSe QDs. Such rapid photo-oxidation does not introduce more nonradiative defects, instead, it enhances the coupling between QDs through surface modification and the PL intensity can be significantly improved.

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