Wang Ying, Zou Renmeng, Chang Jin, Fu Zewu, Cao Yu, Zhang Liangdong, Wei Yingqiang, Kong Decheng, Zou Wei, Wen Kaichuan, Fan Ning, Wang Nana, Huang Wei, Wang Jianpu
Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) , Nanjing Tech University (NanjingTech) , 30 South Puzhu Road , Nanjing 211816 , China.
Shaanxi Institute of Flexible Electronics (SIFE) , Northwestern Polytechnical University (NPU) , 127 West Youyi Road , Xi'an 710072 , China.
J Phys Chem Lett. 2019 Feb 7;10(3):453-459. doi: 10.1021/acs.jpclett.8b03700. Epub 2019 Jan 16.
Tin-based halide perovskites have attracted considerable attention for nontoxic perovskite light-emitting diodes (PeLEDs), but the easy oxidation of Sn and nonuniform film morphology cause poor device stability and reproducibility. Herein, we report a facile approach to achieve efficient and stable lead-free PeLEDs by using tin-based perovskite multiple quantum wells (MQWs) for the first time. On the basis of various spectroscopic investigations, we find that the MQW structure not only facilitates the formation of uniform and highly emissive perovskite films but also suppresses the oxidation of Sn cations. The tin-based MQW PeLED exhibits a peak external quantum efficiency of 3% and a high radiance of 40 W sr m with good reproducibility. Significantly, these devices show excellent operational stability with over a 2 h lifetime under a constant current density of 10 mA cm, which is comparable to that of lead-based PeLEDs. These results suggest that perovskite MQWs can provide a promising platform for achieving high-performance lead-free PeLEDs.
锡基卤化物钙钛矿因其可用于无毒钙钛矿发光二极管（PeLED）而备受关注，但锡的易氧化性和不均匀的薄膜形态导致器件稳定性和可重复性较差。在此，我们首次报道了一种通过使用锡基钙钛矿多量子阱（MQW）来实现高效稳定无铅PeLED的简便方法。基于各种光谱研究，我们发现MQW结构不仅有助于形成均匀且高发射率的钙钛矿薄膜，还能抑制Sn阳离子的氧化。基于锡的MQW PeLED表现出3%的峰值外量子效率和40 W sr⁻¹ m⁻²的高辐射率，且具有良好的可重复性。值得注意的是，这些器件在10 mA cm⁻²的恒定电流密度下显示出超过2小时的寿命，具有出色的运行稳定性，这与基于铅的PeLED相当。这些结果表明，钙钛矿MQW可以为实现高性能无铅PeLED提供一个有前景的平台。
