Contact
    Start Publications Self-assembled monolayer–based blue perovskite LEDs
    ←  Publication Finder
    Attension

    Self-assembled monolayer–based blue perovskite LEDs

    Year: 2023

    Journal: Science Advances, Volume 9, 2023-09-08

    Authors: Wang, Ya-Kun; Jia, Fengyan; Li, Xiaoyue; Teale, Sam; Xia, Pan; Liu, Yuan; Chan, Phoebe Tsz-shan; Wan, Haoyue; Hassan, Yasser; Imran, Muhammad; Chen, Hao; Grater, Luke; Sun, Ling-Dong; Walker, Gilbert C.; Hoogland, Sjoerd; Lu, Zheng-Hong; Yan, Chun-Hua; Liao, Liang-Sheng; Sargent, Edward H.

    Blue perovskite light-emitting diodes (LEDs) have shown external quantum efficiencies (EQEs) of more than 10%; however, devices that emit in the true blue—those that accord with the emission wavelength required for Rec. 2100 primary blue—have so far been limited to EQEs of ~6%. We focused here on true blue emitting CsPbBr3 colloidal nanocrystals (c-NCs), finding in early studies that they suffer from a high charge injection barrier, a problem exacerbated in films containing multiple layers of nanocrystals. We introduce a self-assembled monolayer (SAM) active layer that improves charge injection. We identified a bifunctional capping ligand that simultaneously enables the self-assembly of CsPbBr3 c-NCs while passivating surface traps. We report, as a result, SAM-based LEDs exhibit a champion EQE of ~12% [CIE of (0.132, 0.069) at 4.0 V with a luminance of 11 cd/m2], and 10-fold–enhanced operating stability relative to the best previously reported Rec. 2100-blue perovskite LEDs.
    View publication