4. Student Poster Presentation #4 (Session 1)
Bright White-Light-Emitting Mn-Doped One-Dimensional Lead
Bromide Perovskites
Chenkun Zhou 1 , Yu Tian 2 , Oussama Khabou 3 , Michael Worku 2 , Haoran Lin 1 , Yan Zhou 3 , Biwu
Ma 123
1
Department of Chemical and Biomedical Engineering, 2 Materials Science Program, 3 Department of
Chemistry and Biochemistry
Abstract
Novel white light emitting diodes (WLEDs) based on luminescent nanocrystal materials attract considerable
recent interest due to their promising applications in solid-state lighting. Two approaches are the most common
to fabricate WLEDs. One is to coating a yellow phosphor or the mixture of green and red phosphors on a blue-
LED chip. The other is to simply mixing different nanocrystals of the three primary colors (blue, green, and red)
to generate white emission on an UV-LED. However, WLEDs based on these approaches are observed to suffer
from poor stability over time due to the re-absorption of light and undesired energy transfer. Alternatively, the
use of single-emitting component has great advantages in WLEDs over multi-component materials, such as
higher stability, low-cost fabrication, and greater reproducibility.
Recently, our group reported a new one-dimensional (1D) organic lead bromide perovskite with broadband
emissions and extremely large full width at half maximum (FWHM), which results from strong quantum
confinement with the formation of self-trapped excited states 1 . However, the strong quantum confinement in 1D
structures leads to blue shift of the light emission, resulting in deficiency of red emission and low color rendering
index (CRI). To improve the quality of white emission with higher CRI, integrating red emitting species in these
1D lead bromide perovskites without quenching the blue emission is desired.
Herein, we report the synthesis and characterization of a new class of white emitting phosphors based on Mn 2+
doped one-dimensional organic lead bromide perovskites to overcome these drawbacks. These new phosphors
can be prepared by facile one-step synthesis at room temperature in high yield. The bright white emission from
these materials is the combination of blue emission from the indirect self-trapped excited states of the 1D
perovskites and red emission from the doped Mn 2+ ion. Due to the indirect nature of the self-trapped excited
states, there is no energy transfer from them to the Mn 2+ ions, resulting in independent dual emission. As
compared to the pristine 1D perovskites with bluish white emission, these Mn 2+ doped 1D perovskites exhibit
much higher CRI and photoluminescence quantum efficiency.
Reference
Yuan, Z.; Zhou, C.; Tian, Y.; Shu, Y.; Messier, J.; Wang, J. C.; van de Burgt, L. J.; Kountouriotis, K.; Xin, Y.; Holt, E.;
Schanze, K.; Clark, R.; Siegrist, T.; Ma, B., One-dimensional organic lead halide perovskites with efficient bluish white-
light emission. Nature Communications 2017, 8, 14051.
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