Excitation Energy Dependence of the Photoluminescence Quantum Yield of Core/Shell CdSe/CdS Quantum Dots and Correlation with Circular Dichroism,Chemistry of Materials

当前位置： X-MOL 学术 › Chem. Mater. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Excitation Energy Dependence of the Photoluminescence Quantum Yield of Core/Shell CdSe/CdS Quantum Dots and Correlation with Circular Dichroism
Chemistry of Materials ( IF 7.2 ) Pub Date : 2018-01-05 00:00:00 , DOI: 10.1021/acs.chemmater.7b04478
Irina V. Martynenko _{1,

2} , Anvar S. Baimuratov ₁ , Victoria A. Osipova ₁ , Vera A. Kuznetsova ₃ , Finn Purcell-Milton ₃ , Ivan D. Rukhlenko _{1,

4} , Anatoly V. Fedorov ₁ , Yurii K. Gun’ko _{1,

3} , Ute Resch-Genger ₂ , Alexander V. Baranov ₁

Affiliation

Quantum dot (QD) based nanomaterials are very promising materials for the fabrication of optoelectronic devices like solar cells, light emitting diodes (LEDs), and photodetectors as well as as reporters for chemo- and biosensing and bioimaging. Many of these applications involve the monitoring of changes in photoluminescence intensity and energy transfer processes which can strongly depend on excitation wavelength or energy. In this work, we analyzed the excitation energy dependence (EED) of the photoluminescence quantum yields (PL QYs) and decay kinetics and the circular dichroism (CD) spectra of CdSe/CdS core/shell QDs with different thicknesses of the surface passivation shell. Our results demonstrate a strong correlation between the spectral position of local maxima observed in the EED of PL QY and the zero-crossing points of the CD profiles. Theoretical analysis of the energy band structure of the QDs with effective mass approximation suggests that these structures could correspond to exciton energy levels. This underlines the potential of CD spectroscopy for the study of electronic energy structure of chiroptically active nanocrystals which reveal quantum confinement effects.

中文翻译：

核/壳CdSe / CdS量子点的光致发光量子产率的激发能依赖性及其与圆二色性的关系

基于量子点（QD）的纳米材料是非常有前途的材料，可用于制造光电子器件，例如太阳能电池，发光二极管（LED）和光电探测器，以及化学和生物传感及生物成像的报告分子。这些应用中的许多应用都涉及对光致发光强度和能量转移过程变化的监控，这些变化可能严重取决于激发波长或能量。在这项工作中，我们分析了具有不同厚度的表面钝化壳的CdSe / CdS核/壳QD的光致发光量子产率（PL QYs）的激发能依赖性（EED），衰变动力学和圆二色性（CD）光谱。我们的结果表明，在PL QY的EED中观察到的局部最大值的光谱位置与CD轮廓的零交叉点之间具有很强的相关性。对量子点的能带结构进行有效质量近似的理论分析表明，这些结构可能与激子能级相对应。这突显了CD光谱法用于研究整脊活性纳米晶体的电子能量结构的潜力，揭示了量子限制效应。

更新日期：2018-01-05

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11