Back to Search Start Over

Mechanisms of LiF Interlayer Enhancements of Perovskite Light-Emitting Diodes

Authors :
Rafael Quintero-Bermudez
Rafael Quintero-Torres
Jeffrey Kirman
Dongxin Ma
Edward H. Sargent
Source :
The Journal of Physical Chemistry Letters. 11:4213-4220
Publication Year :
2020
Publisher :
American Chemical Society (ACS), 2020.

Abstract

The use of LiF as a thin interlayer between the electron transport layer and cathode has played a pivotal role in remarkable advances in perovskite LEDs (PeLEDs); however, the mechanism behind the effect of LiF remains to be fully understood. Here, we report a combined experimental and computational study, from which we ascribe the benefits of a LiF interlayer to the migration of dissociated Li into the cathode and dissociated F into the anode. Electronic device simulations reveal that the former improves electron injection by lowering the Schottky barrier height, while the latter reduces the barrier width. These reduce turn-on voltage and improve current density and charge balance in LEDs. We fabricate PeLEDs with and without the LiF interlayer and link these materials and electronic phenomena to the device light-current-voltage characteristics. X-ray photoelectron spectroscopy obtained in sputter profiling of PeLEDs corroborates the dissociation of LiF.

Details

ISSN :
19487185
Volume :
11
Database :
OpenAIRE
Journal :
The Journal of Physical Chemistry Letters
Accession number :
edsair.doi.dedup.....6142238c40fcac2c6766285748b3e267
Full Text :
https://doi.org/10.1021/acs.jpclett.0c00757