Rational Ion Migration Management for Long-Term Stable Blue Perovskite Light-Emitting Diodes

长期稳定蓝色钙钛矿发光二极管的合理离子迁移管理

• 批准号: EP/Y029135/1
• 负责人: Zhongcheng Yuan
• 金额: $ 25.55万
• 依托单位: University of Oxford
• 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%2FY029135%2F1
• 关键词: Rational; Ion; Migration; Management; Long

Metal halide perovskites, which possess high conductivity, high photoluminescence quantum efficiency and color purity, are ideal emitters for cost-effective light-emitting diodes (LEDs). Although EQEs of perovskite LEDs (PeLEDs) emitting in red and green have been boosted to over 25 % recently, approaching that of prevailing OLED and QLEDs, it is still a great challenge to achieve high efficiency blue PeLEDs. More importantly, overcoming poor operational lifetime of PeLEDs (around 10 hours for blue PeLEDs), which is thought to originate from severe ion migration induced by electric field in perovskite emitters and interfacial degradation, is a key for further development of PeLEDs and future applications in displays and lighting. The objective of RAIMM is achieving pure blue PeLEDs (emitting from 465 to 475 nm) with EQEs exceeding 20 % and significantly improved lifetime over 1,000 hours @100 cd/m2. My strategies are using several powerful characterizations (e.g., in-situ PL, in-situ EL imaging, PL&EL, etc.) to reveal a clear degradation mechanism of perovskite emitters and PeLEDs. Accordingly, I will introduce different processing additives to achieve highly emissive perovskite emitters with much suppressed ion migration. With the stable perovskite emitters, new device structures will be designed to stabilize the interfacial contacts and decrease turn-on voltages of PeLEDs. This strategy will minimize the electrical fields across the PeLEDs and limit ion penetration through charge transporting layers. Finally, I will be able to achieve high efficiency pure blue PeLEDs with lifetime over 1,000 h, representing a milestone in PeLEDs community. I will collaborate with Helio Display Materials to demonstrate the first all perovskite-based prototype display with Rec. 2020 color gamut. I believe our results will dramatically accelerate the progress of PeLEDs and stimulate further breakthroughs in other perovskite optoelectronic devices.

金属卤化物钙钛矿具有高电导率、高光致发光量子效率和颜色纯度，是制作高性价比发光二极管的理想发光体。尽管红光和绿光的钙钛矿型发光二极管(PeLED)的EQE已经提高到25%以上，接近流行的OLED和QLED，但实现高效率的蓝色PeLED仍然是一个巨大的挑战。更重要的是，克服PeLED较差的工作寿命(蓝色PeLED约为10小时)，这被认为是由钙钛矿型发射体中的电场引起的严重离子迁移和界面退化造成的，这是进一步发展PeLED以及未来在显示和照明方面应用的关键。RAIMM的目标是实现纯蓝色PeLED(发光范围从465到475 nm)，EQE超过20%，并在100 cd/m2的情况下显著延长1000小时以上的寿命。我的策略使用了几个强大的特征(例如，原位发光、原位发光成像、发光和电致发光等)。为了揭示钙钛矿发射体和PeLED的清晰降解机理。因此，我将介绍不同的加工添加剂，以获得高发射率的钙钛矿型发射器，同时抑制离子迁移。有了稳定的钙钛矿型发射体，新的器件结构将被设计来稳定界面接触和降低PeLED的开启电压。这一策略将使PeLED两端的电场最小化，并限制离子通过电荷传输层的渗透。最终，我将能够实现寿命超过1,000小时的高效率纯蓝色PeLED，这是PeLED领域的一个里程碑。我将与Helio Display Material合作，与Rec一起演示第一个完全基于钙钛矿的原型显示器。2020色域。我相信，我们的成果将极大地加快PeLED的进展，并刺激其他钙钛矿型光电子器件的进一步突破。