Microsecond-response perovskite light-emitting diodes for active-matrix displays
Yun Gao, Hongjin Li, Xingliang Dai, Xingjian Ying, Zhe Liu, Jiajun Qin, Jie Guo, Zhongkang Han, Yujing Zhang, Meiyi Zhu, Xiaohui Wu, Qiuting Cai, Yixing Yang, Linrun Feng, Xiaoyu Zhang, Jingyun Huang, Haiping He, Feng Gao, Zhizhen Ye
Abstract
Abstract Perovskite light-emitting diodes (PeLEDs) could be of use in the development of active-matrix displays. However, due to ion migration in crystal structure, PeLEDs have electroluminescence rise times over milliseconds, which is problematic for the development of high-refresh-rate displays. Here, we show that the electroluminescence rise time of PeLEDs can be reduced to microseconds using an individual-particle passivation strategy. The approach is based on BF 4 − ions that can passivate every nanocrystal in a perovskite emissive layer during film deposition. It leads to a defect-free film with discrete nanostructure and excellent crystallinity, which inhibits ion migration. Our strategy can be applied in perovskite nanocrystal films with different colours: red (635 nm), green (520 nm) and blue (475 nm). These PeLEDs all demonstrate response times within microseconds and high external quantum efficiencies of 22.7%, 26.2% and 18.1%, respectively. This allows us to create microsecond-response active-matrix PeLEDs that exhibit external quantum efficiencies above 20% at a display brightness of 500–3,000 cd m −2 for green devices with a resolution of 30 pixels per inch. We also develop microsecond-response red, green and blue active-matrix displays with 90 pixels per inch.