Prodanov Maksym F, Gupta Swadesh K, Kang Chengbin, Diakov Maksym Y, Vashchenko Valerii V, Srivastava Abhishek K
State Key Laboratory on Advanced Displays and Optoelectronics Technologies, Department of Electronics and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
Small. 2021 Jan;17(3):e2004487. doi: 10.1002/smll.202004487. Epub 2020 Dec 20.
Recently, quantum rods (QRs) have been studied heavily for display and lighting applications. QRs offer serious advantages over the quantum dots such as higher light out-coupling coefficient, and polarized emission. The QR enhancement films double liquid crystal display efficiency. However, it is still a challenge to synthesize good quality green (λ ≈ 520 nm) and blue (λ ≈ 465 nm) emitting QRs, due to very large bathochromic shift during the shell growth. Furthermore, until now, the presence of cadmium in high-quality QRs is inevitable, but due to its toxicity, RoHS has restricted the amount of cadmium in consumer products. In this article, low Cd core-shell QRs, with a narrow-band luminescence spectrum tuned in the whole visible range, are prepared by replacing Cd with Zn in a one-pot post-synthetic development. These QRs possess the good thermal stability of photoluminescence properties, and therefore, show high performance for the on-chip LED configuration. The designed white LEDs (WLEDs) are characterized by a high brightness of 120000 nits, and color gamut covering 122% NTSC (90% of BT2020), in the 1931CIE color space. Additionally, these LEDs show a high luminous efficiency of 115 lm W . Thus, these quantum rod LED are perfectly viable for display backlighting and lighting applications.
最近，量子棒（QRs）在显示和照明应用方面得到了大量研究。与量子点相比，量子棒具有显著优势，如更高的光出耦合系数和偏振发射。量子棒增强膜可使液晶显示器效率提高一倍。然而，由于在壳生长过程中存在非常大的红移，合成高质量的绿色（λ≈520nm）和蓝色（λ≈465nm）发射量子棒仍然是一个挑战。此外，到目前为止，高质量量子棒中镉的存在是不可避免的，但由于其毒性，《限制有害物质指令》（RoHS）已对消费产品中的镉含量作出限制。在本文中，通过在一锅法合成后处理中用锌替代镉，制备了窄带发光光谱在整个可见光范围内可调的低镉核壳量子棒。这些量子棒具有良好的光致发光性能热稳定性，因此，在片上发光二极管（LED）配置中表现出高性能。所设计的白色发光二极管（WLED）在1931CIE颜色空间中的特征在于具有120000尼特的高亮度和覆盖122% NTSC（BT2020的90%）的色域。此外，这些发光二极管显示出115 lm/W的高发光效率。因此，这些量子棒发光二极管在显示背光和照明应用中完全可行。
