Edge stabilization in reduced-dimensional perovskites
Date
2020
Authors
Na Quan, Li
Ma, Dongxin
Zhao, Yongbiao
Voznyy, Oleksandr
Yuan, Haifeng
Bladt, Eva
Pan, Jun
García de Arquer, F. Pelayo
Sabatini, Randy
Piontkowski, Zachary
Journal Title
Journal ISSN
Volume Title
Publisher
Nature Communications
Abstract
Reduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite light-emitting diodes is their limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack is powered by photogenerated and electrically-injected carriers that diffuse to the nanoplatelet edges and produce superoxide. We report an edge-stabilization strategy wherein phosphine oxides passivate unsaturated lead sites during perovskite crystallization. With this approach, we synthesize reduced-dimensional perovskites that exhibit 97±3% photoluminescence quantum yields and stabilities that exceed 300 h upon continuous illumination in an air ambient. We achieve green-emitting devices with a peak external quantum efficiency (EQE) of 14% at 1000 cd m2; their maximum luminance is 4.5×104 cd m2 (corresponding to an EQE of 5%); and, at 4000 cd m2, they achieve an operational half-lifetime of 3.5 h.
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Citation
Quan, L. N., Ma, D., Zhao, Y., Voznyy, O., Yuan, H., Bladt, E., Pan, J., De Arquer, F. P. G., Sabatini, R., Piontkowski, Z., Emwas, A., Todorović, P., Quintero-Bermudez, R., Walters, G., Fan, J. Z., Liu, M., Tan, H., Saidaminov, M. I., Gao, L., . . . Sargent, E. H. (2020). Edge stabilization in reduced-dimensional perovskites. Nature Communications, 11(1). https://doi.org/10.1038/s41467-019-13944-2