Light-emitting diodes (LEDs) based on excitonic material systems, in which tightly bound photoexcited electron–hole pairs migrate together rather than as individual charge carriers, offer an attractive route to developing solution-processed, high-performance light emitters. Here, we demonstrate bright, efficient, excitonic infrared LEDs through the incorporation of quantum dots (QDs)1 into a low-dimensional perovskite matrix. We program the surface of the QDs to trigger fast perovskite nucleation to achieve homogeneous incorporation of QDs into the matrix without detrimental QD aggregation, as verified by in situ grazing incidence wide-angle X-ray spectroscopy. We tailor the distribution of the perovskites to drive balanced ultrafast excitonic energy transfer to the QDs. The resulting LEDs operate in the short-wavelength infrared region, an important regime for imaging and sensing applications, and exhibit a high external quantum efficiency of 8.1% at 980 nm at a radiance of up to 7.4 W Sr−1 m−2.
KAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): OSR-2017-CPF-3321-03
Acknowledgements: This publication is based in part on work supported by the Natural Sciences and Engineering Research Council of Canada, by the Ontario Research Fund Research Excellence Program, by Toyota Motors Europe and by award OSR-2017-CPF-3321-03 made by King Abdullah University of Science and Technology (KAUST). We thank R. Munir for the GIWAXS/GISAXS measurements performed at the Cornell High Energy Synchrotron Source (CHESS), supported by NSF award DMR-1332208. We thank D. Kopilovic, E. Palmiano, L. Levina and R. Wolowiec for technical support.