Matching Solid-State to Solution-Phase Photoluminescence for Near-Unity Down-Conversion Efficiency Using Giant Quantum Dots

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• 作者：Christina J. Hanson ; Matthew R. Buck ; Krishna Acharya ; Joseph A. Torres ; Janardan Kundu ; Xuedan Ma ; Sarah Bouquin ; Christopher E. Hamilton ; Han Htoon ; Jennifer A. Hollingsworth
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2015
• 出版时间：June 24, 2015
• 年：2015
• 卷：7
• 期：24
• 页码：13125-13130
• 全文大小：287K
• ISSN：1944-8252

文摘

Efficient, stable, and narrowband red-emitting fluorophores are needed as down-conversion materials for next-generation solid-state lighting that is both efficient and of high color quality. Semiconductor quantum dots (QDs) are nearly ideal color-shifting phosphors, but solution-phase efficiencies have not traditionally extended to the solid-state, with losses from both intrinsic and environmental effects. Here, we assess the impacts of temperature and flux on QD phosphor performance. By controlling QD core/shell structure, we realize near-unity down-conversion efficiency and enhanced operational stability. Furthermore, we show that a simple modification of the phosphor-coated light-emitting diode device鈥搃ncorporation of a thin spacer layer鈥揷an afford reduced thermal or photon-flux quenching at high driving currents (>200 mA).