Ultra-bright and highly efficient inorganic based perovskite light-emitting diodes.
Ultra-bright and highly efficient inorganic based perovskite light-emitting diodes.
复制标题
超亮高效无机钙钛矿发光二极管
DOI：
10.1038/ncomms15640
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发表时间：
2017-06-07
影响因子：
16.6
通讯作者：
You J
中科院分区：
文献类型：
--
作者：
Zhang L;Yang X;Jiang Q;Wang P;Yin Z;Zhang X;Tan H;Yang YM;Wei M;Sutherland BR;Sargent EH;You J
无机钙钛矿材料CsPbX3(X=Cl，Br，I)因其优异的热稳定性和较高的光致发光量子效率而备受关注。然而，它们的发光二极管的电致发光量子效率为1%。我们推测，这种低效率是由于钙钛矿形貌差、界面和钙钛矿晶界的高非辐射复合以及电荷注入不平衡导致的高泄漏电流的结果。在这里，我们在CsPbBr3晶格中加入了少量的甲基铵有机阳离子，并通过在氧化锌电子注入层顶部沉积一种亲水性和绝缘性的聚乙烯吡咯烷聚合物来克服这些问题。以混合阳离子钙钛矿Cs0.87MA0.13PbBr3为发光层，得到了亮度高达91,000 Cd m−2，外量子效率高达10.4%的发光二极管。据我们所知，这是迄今为止报道的最明亮、效率最高的绿色钙钛矿型发光二极管。
Inorganic perovskites such as CsPbX3(X=Cl, Br, I) have attracted attention due to their excellent thermal stability and high photoluminescence quantum efficiency. However, the electroluminescence quantum efficiency of their light-emitting diodes was <1%. We posited that this low efficiency was a result of high leakage current caused by poor perovskite morphology, high non-radiative recombination at interfaces and perovskite grain boundaries, and also charge injection imbalance. Here, we incorporated a small amount of methylammonium organic cation into the CsPbBr3lattice and by depositing a hydrophilic and insulating polyvinyl pyrrolidine polymer atop the ZnO electron-injection layer to overcome these issues. As a result, we obtained light-emitting diodes exhibiting a high brightness of 91,000 cd m−2and a high external quantum efficiency of 10.4% using a mixed-cation perovskite Cs0.87MA0.13PbBr3as the emitting layer. To the best of our knowledge, this is the brightest and most-efficient green perovskite light-emitting diodes reported to date.