Nah Yoonseo, Solanki Devan, Dong Yitong, Röhr Jason A, Taylor André D, Hu Shu, Sargent Edward H, Kim Dong Ha
Division of Chemical Engineering and Materials Science, College of Engineering, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, 03760, Republic of Korea.
Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, 06511, USA.
Adv Sci (Weinh). 2022 Aug;9(24):e2201807. doi: 10.1002/advs.202201807. Epub 2022 Jul 6.
Solution-processed quasi-2D perovskites contain multiple quantum wells with a broad width distribution. Inhomogeneity results in the charge funneling into the smallest bandgap components, which hinders deep-blue emission and accelerates Auger recombination. Here, a synthetic strategy applied to a range of quasi-2D perovskite systems is reported, that significantly narrows the quantum well dispersity. It is shown that the phase distribution in the perovskite film is significantly narrowed with controlled, simultaneous evaporation of solvent and antisolvent. Modulation of film formation kinetics of quasi-2D perovskite enables stable deep-blue electroluminescence with a peak emission wavelength of 466 nm and a narrow linewidth of 14 nm. Light emitting diodes using the perovskite film show a maximum luminance of 280 cd m at an external quantum efficiency of 0.1%. This synthetic approach will serve in producing new materials widening the color gamut of next-generation displays.
溶液法制备的准二维钙钛矿包含多个量子阱，其宽度分布较宽。不均匀性导致电荷流入带隙最小的组分，这阻碍了深蓝色发射并加速了俄歇复合。在此，报道了一种应用于一系列准二维钙钛矿体系的合成策略，该策略显著缩小了量子阱的分散性。结果表明，通过控制溶剂和反溶剂的同时蒸发，钙钛矿薄膜中的相分布显著变窄。对准二维钙钛矿成膜动力学的调控实现了稳定的深蓝色电致发光，其峰值发射波长为466nm，线宽为14nm。使用该钙钛矿薄膜的发光二极管在外部量子效率为0.1%时，最大亮度为280cd m。这种合成方法将有助于生产拓宽下一代显示器色域的新材料。
