Wood Vanessa, Bulović Vladimir
Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nano Rev. 2010;1. doi: 10.3402/nano.v1i0.5202. Epub 2010 Jul 7.
Colloidal quantum dot light-emitting devices (QD-LEDs) have generated considerable interest for applications such as thin film displays with improved color saturation and white lighting with a high color rendering index (CRI). We review the key advantages of using quantum dots (QDs) in display and lighting applications, including their color purity, solution processability, and stability. After highlighting the main developments in QD-LED technology in the past 15 years, we describe the three mechanisms for exciting QDs - optical excitation, Förster energy transfer, and direct charge injection - that have been leveraged to create QD-LEDs. We outline the challenges facing QD-LED development, such as QD charging and QD luminescence quenching in QD thin films. We describe how optical downconversion schemes have enabled researchers to overcome these challenges and develop commercial lighting products that incorporate QDs to achieve desirable color temperature and a high CRI while maintaining efficiencies comparable to inorganic white LEDs (>65 lumens per Watt). We conclude by discussing some current directions in QD research that focus on achieving higher efficiency and air-stable QD-LEDs using electrical excitation of the luminescent QDs.
胶体量子点发光器件（QD-LED）在诸如具有更高色彩饱和度的薄膜显示器以及具有高显色指数（CRI）的白光照明等应用中引起了广泛关注。我们回顾了在显示和照明应用中使用量子点（QD）的关键优势，包括其颜色纯度、溶液可加工性和稳定性。在强调了过去15年中QD-LED技术的主要发展之后，我们描述了用于激发量子点的三种机制——光激发、福斯特能量转移和直接电荷注入，这些机制已被用于制造QD-LED。我们概述了QD-LED发展面临的挑战，例如量子点薄膜中的量子点充电和量子点发光猝灭。我们描述了光学下转换方案如何使研究人员能够克服这些挑战，并开发出包含量子点的商业照明产品，以实现理想的色温以及高显色指数，同时保持与无机白光LED相当的效率（>65流明/瓦）。我们通过讨论量子点研究的一些当前方向来结束本文，这些方向专注于通过对发光量子点进行电激发来实现更高效率和空气稳定的QD-LED。
