Ultrabright and stable top-emitting quantum-dot light-emitting diodes with negligible angular color shift

Mengqi Li¹, Rui Li¹, Longjia Wu², Xiongfeng Lin¹, Xueqing Xia¹, Zitong Ao², Xiaojuan Sun¹, Xingtong Chen¹,Song Chen^1,3*（陈崧）

¹Suzhou KeyLaboratory ofNovelSemiconductor-optoelectronics Materials and Devices, College of Chemistry, Chemical Engineering and MaterialsScience, Soochow University, Suzhou 215123 Jiangsu, China.

²TCL Corporate Research, 1001 Zhongshan Park Road, Nanshan District, Shenzhen 518067 Guangdong, China.

³Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123 Jiangsu, China.

Nat. Commun.,2024,15,5161

Abstract:Top emission can enhance luminance, color purity, and panel-manufacturing compatibility for emissive displays. Still, top-emitting quantum-dot light-emitting diodes (QLEDs) suffer from poor stability, low light outcoupling, and non-negligible viewing-angle dependence because, for QLEDs with non-red emission, the electrically optimum device structure is incompatible with single-mode optical microcavity. Here, we demonstrate that by improving the way of determining reflection penetration depths and creating refractive-index-lowering processes, the issues faced by green QLEDs can be overcome. This leads to advanced device performance, including a luminance exceeding 1.6 million nits, a current efficiency of 204.2 cd A⁻¹, and a T₉₅operational lifetime of 15,600 hours at 1000 nits. Meanwhile, our design does not compromise light outcoupling as it offers an external quantum efficiency of 29.2% without implementing light extraction methods. Lastly, an angular color shift of Δu^’v^’ = 0.0052 from 0° to 60° is achieved by narrowing the emission linewidth of quantum dots.

链接：https://www.nature.com/articles/s41467-024-49574-6