Surface-2D/Bulk-3D Heterophased Perovskite Nanograins for Long-Term-Stable Light-Emitting Diodes.,Advanced Materials

当前位置： X-MOL 学术 › Adv. Mater. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Surface-2D/Bulk-3D Heterophased Perovskite Nanograins for Long-Term-Stable Light-Emitting Diodes.
Advanced Materials ( IF 27.4 ) Pub Date : 2019-11-18 , DOI: 10.1002/adma.201905674
Tae-Hee Han _{1,

2} , Jin-Wook Lee _{1,

3} , Yung Ji Choi ₄ , Chungseok Choi ₁ , Shaun Tan ₁ , Sung-Joon Lee ₁ , Yepin Zhao ₁ , Yu Huang ₁ , Dongho Kim ₄ , Yang Yang ₁

Affiliation

Although metal halide perovskite (MHP) light-emitting diodes (LEDs) have demonstrated great potential in terms of electroluminescence efficiency, the operational stability of MHP LEDs currently remains the biggest bottleneck toward their practical usage. Well-confined excitons/charge carriers in a dielectric/quantum well based on conventional spatial or potential confinement approaches substantially enhance radiative recombination in MHPs, but an increased surface-to-volume ratio and multiphase interfaces likely result in a high degree of surface or interface defect states, which brings about a critical environmentally/operationally vulnerable point on LED stability. Here, an effective solution is suggested to mitigate such drawbacks using strategically designed surface-2D/bulk-3D heterophased MHP nanograins for long-term-stable LEDs. The 2D surface-functionalized MHP renders significantly reduced trap density, environmental stability, and an ion-migration-immune surface in addition to a fast radiative recombination owing to its spatially and potentially confined charge carriers, simultaneously. As a result, heterophased MHP LEDs show substantial improvement in operational lifetime (T50 : >200 h) compared to conventional pure 3D or quasi-2D counterparts (T50 : < 0.2 h) as well as electroluminescence efficiency (surface-2D/bulk-3D: ≈7.70 ph per el% and pure 3D: ≈0.46 ph per el%).

中文翻译：

适用于长期稳定发光二极管的Surface-2D / Bulk-3D异相钙钛矿纳米颗粒。

尽管就电致发光效率而言，金属卤化物钙钛矿（MHP）发光二极管（LED）已显示出巨大的潜力，但是MHP LED的操作稳定性目前仍然是其实际应用的最大瓶颈。基于常规空间或电势限制方法的介电/量子阱中限制良好的激子/电荷载流子，可以显着增强MHP中的辐射复合，但是增加的表面体积比和多相界面可能会导致高度的表面或界面缺陷状态，这会在LED稳定性方面带来关键的环境/操作脆弱点。在这里，提出了一种有效的解决方案，可以使用战略性设计的表面2D /本体3D异相MHP纳米颗粒针对长期稳定的LED减轻此类缺陷。2D表面功能化的MHP不仅由于其空间和潜在受限的载流子，还具有快速的辐射重组能力，从而显着降低了陷阱密度，环境稳定性和离子迁移免疫表面。结果，与传统的纯3D或准2D同类产品（T50：<0.2小时）相比，异相MHP LED的使用寿命（T50：> 200小时）显着提高，电致发光效率（表面2D /本体3D）：≈7.70 ph / el％和纯3D：≈0.46ph / el％）。

更新日期：2020-01-07

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南11