Self-Generated Buried Submicrocavities for High-Performance Near-Infrared Perovskite Light-Emitting Diode

Jiong Li; Chenghao Duan; Qianpeng Zhang; Chang Chen; Qiaoyun Wen; Minchao Qin; Christopher C S Chan; Shibing Zou; Jianwu Wei; Zuo Xiao; Chuantian Zuo; Xinhui Lu; Kam Sing Wong; Zhiyong Fan; Keyou Yan

doi:10.1007/s40820-023-01097-3

Self-Generated Buried Submicrocavities for High-Performance Near-Infrared Perovskite Light-Emitting Diode

Nanomicro Lett. 2023 May 15;15(1):125. doi: 10.1007/s40820-023-01097-3.

Authors

Jiong Li¹, Chenghao Duan^{1

2}, Qianpeng Zhang³, Chang Chen¹, Qiaoyun Wen¹, Minchao Qin², Christopher C S Chan⁴, Shibing Zou¹, Jianwu Wei⁵, Zuo Xiao⁶, Chuantian Zuo⁶, Xinhui Lu², Kam Sing Wong⁴, Zhiyong Fan⁷, Keyou Yan⁸

Affiliations

¹ School of Environment and Energy, State Key Lab of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510000, People's Republic of China.
² Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, People's Republic of China.
³ Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People's Republic of China.
⁴ Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, 999077, Hong Kong, People's Republic of China.
⁵ School of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, People's Republic of China.
⁶ Center for Excellence in Nanoscience (CAS), Key Laboratory of Nanosystem and Hierarchical Fabrication (CAS), National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China.
⁷ Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People's Republic of China. eezfan@ust.hk.
⁸ School of Environment and Energy, State Key Lab of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510000, People's Republic of China. kyyan@scut.edu.cn.

Abstract

Embedding submicrocavities is an effective approach to improve the light out-coupling efficiency (LOCE) for planar perovskite light-emitting diodes (PeLEDs). In this work, we employ phenethylammonium iodide (PEAI) to trigger the Ostwald ripening for the downward recrystallization of perovskite, resulting in spontaneous formation of buried submicrocavities as light output coupler. The simulation suggests the buried submicrocavities can improve the LOCE from 26.8 to 36.2% for near-infrared light. Therefore, PeLED yields peak external quantum efficiency (EQE) increasing from 17.3% at current density of 114 mA cm^-2 to 25.5% at current density of 109 mA cm^-2 and a radiance increasing from 109 to 487 W sr^-1 m^-2 with low rolling-off. The turn-on voltage decreased from 1.25 to 1.15 V at 0.1 W sr^-1 m^-2. Besides, downward recrystallization process slightly reduces the trap density from 8.90 × 10¹⁵ to 7.27 × 10¹⁵ cm^-3. This work provides a self-assembly method to integrate buried output coupler for boosting the performance of PeLEDs.

Keywords: Buried submicrocavities; Downward recrystallization; Light out-coupling efficiency; Perovskite light-emitting diodes; Radiative recombination.