High Color-Purity and Efficient Pure-Blue Perovskite Light-Emitting Diodes Based on Strongly Confined Monodispersed Quantum Dots

Aqiang Liu; Chenghao Bi; Jing Li; Mengqi Zhang; Chunyan Cheng; David Binks; Jianjun Tian

doi:10.1021/acs.nanolett.3c00548

High Color-Purity and Efficient Pure-Blue Perovskite Light-Emitting Diodes Based on Strongly Confined Monodispersed Quantum Dots

Nano Lett. 2023 Mar 22;23(6):2405-2411. doi: 10.1021/acs.nanolett.3c00548. Epub 2023 Mar 7.

Authors

Aqiang Liu^{1

2}, Chenghao Bi¹, Jing Li³, Mengqi Zhang¹, Chunyan Cheng¹, David Binks⁴, Jianjun Tian^{1

2}

Affiliations

¹ Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, P. R. China.
² Shunde Innovation School, University of Science and Technology Beijing, Foshan 528399, Guangdong, P. R. China.
³ Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
⁴ Department of Physics and Astronomy and Photon Science Institute, University of Manchester, Manchester M13 9PL, U.K.

PMID: 36881120
DOI: 10.1021/acs.nanolett.3c00548

Abstract

Here, we develop an in situ photoluminescence (PL) system to monitor the nucleation and growth of perovskite nanocrystals and control the monomer supply rate to achieve strongly confined and monodispersed quantum dots (QDs) with average size of 3.4 nm. Pure-blue (460 nm wavelength) CsPbBr₃ QDs with near unity PL quantum yield and narrow size distribution (small size dispersion of 9.6%) were thus produced. Light-emitting diodes (LEDs) based on these QDs were prepared by using an all-solution processing route, which showed narrow electroluminescence with full width at half-maximum of 20 nm and a high color purity of 97.3%. The device also had a high external quantum efficiency of 10.1%, maximum luminance of 11 610 cd m^-2, and continuous operation lifetime of 21 h at the initial luminance of 102 cd m^-2, corresponding to the state-of-art for pure-blue perovskite LEDs.

Keywords: high color-purity; perovskite light-emitting; pure-blue emission; quantum-dot; size distribution.