Elucidating a complete picture of exciton dynamics in operating quantum-dot light-emitting diodes

阐明量子点发光二极管运行中激子动力学的完整图景

• 批准号: EP/Y02771X/1
• 负责人: Yunzhou Deng
• 金额: $ 23.84万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY02771X%2F1
• 关键词: Elucidating; complete; picture; exciton; dynamics

Quantum-dot light-emitting diodes (QLEDs) are promising as energy-saving, color-pure, and flexible light sources for display, lighting, and communication techniques. At present, the performance of QLEDs is hindered by the efficiency roll-off at high currents and the device degradation in long-term operations. Further development of QLEDs demands an in-depth understanding of the fundamental processes in device operations. However, due to the lack of in-situ/operando characterization methods, the ultrafast charge and exciton dynamics in operating QLEDs is still not clear. Here, the project aims to go beyond the state-of-the-art methodologies, and create a set of ultrafast spectroscopic toolkits to elucidate a spatio-temporal resolved picture of exciton dynamics in operating QLEDs. I will realize a) operando time-resolved transient absorption (TA), b) operando spatio-temporal TA microscopy, and c) electrically-pumped time-resolved TA measurements on full stacks of QLEDs. I will gain quantitative insights into exciton dissociation, exciton diffusion, and electron injection dynamics. Finally, new mechanistic interpretations on the efficiency roll-off and degradation of QLEDs will be provided. The project covers the disciplines of optics, material science, and device physics, combining the host group's expertise in ultrafast spectroscopy, and theresearcher's expertise in QLEDs. The fellow will acquire complementary skills and knowledge to reach professional maturity. The outcomes will increase the fundamental understanding of nanomaterials and LEDs, facilitating the optimization of QLEDs towards practical requirements. The project will yield a widely-applicable toolkit for various LEDs. Successful implementation of this project will promote the competitiveness of the host organization in the field of optoelectronics. In the long run, the potential commercialization of QLEDs is expected to reduce electricity consumption and promote sustainable development in Europe.

量子点发光二极管 (QLED) 有望成为显示、照明和通信技术领域的节能、色彩纯正且灵活的光源。目前，QLED 的性能受到高电流下效率下降和长期运行中器件退化的阻碍。 QLED 的进一步开发需要深入了解设备操作的基本过程。然而，由于缺乏原位/操作表征方法，QLED 运行中的超快充电和激子动力学仍不清楚。该项目的目标是超越最先进的方法，创建一套超快光谱工具包，以阐明 QLED 运行中激子动力学的时空解析图像。我将实现a）操作时间分辨瞬态吸收（TA），b）操作时空TA显微镜，以及c）全堆叠QLED上的电泵时间分辨TA测量。我将获得对激子解离、激子扩散和电子注入动力学的定量见解。最后，将提供有关 QLED 效率滚降和退化的新机制解释。该项目涵盖光学、材料科学和器件物理等学科，结合了主办团队在超快光谱方面的专业知识和研究人员在 QLED 方面的专业知识。该研究员将获得补充技能和知识以达到专业成熟度。研究成果将增进对纳米材料和 LED 的基本了解，促进 QLED 的优化以满足实际需求。该项目将为各种 LED 提供广泛适用的工具包。该项目的成功实施将提升主办单位在光电领域的竞争力。从长远来看，QLED的潜在商业化有望减少电力消耗并促进欧洲的可持续发展。