Abstract
Development of light-emitting diodes (LEDs) based on colloidal quantum dots is driven by attractive properties of these fluorophores such as spectrally narrow, tunable emission and facile processibility via solution-based methods. A current obstacle towards improved LED performance is an incomplete understanding of the roles of extrinsic factors, such as non-radiative recombination at surface defects, versus intrinsic processes, such as multicarrier Auger recombination or electron-hole separation due to applied electric field. Here we address this problem with studies that correlate the excited state dynamics of structurally engineered quantum dots with their emissive performance within LEDs. We find that because of significant charging of quantum dots with extra electrons, Auger recombination greatly impacts both LED efficiency and the onset of efficiency roll-off at high currents. Further, we demonstrate two specific approaches for mitigating this problem using heterostructured quantum dots, either by suppressing Auger decay through the introduction of an intermediate alloyed layer, or by using an additional shell that impedes electron transfer into the quantum dot to help balance electron and hole injection.
| Original language | English |
|---|---|
| Article number | 2661 |
| Journal | Nature Communications |
| Volume | 4 |
| DOIs | |
| Publication status | Published - 2013 |
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ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Chemistry(all)
- Physics and Astronomy(all)
Cite this
Controlling the influence of Auger recombination on the performance of quantum-dot light-emitting diodes. / Bae, Wan Ki; Park, Young Shin; Lim, Jaehoon; Lee, Donggu; Padilha, Lazaro A.; McDaniel, Hunter; Robel, Istvan; Lee, Changhee; Pietryga, Jeffrey M.; Klimov, Victor I.
In: Nature Communications, Vol. 4, 2661, 2013.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Controlling the influence of Auger recombination on the performance of quantum-dot light-emitting diodes
AU - Bae, Wan Ki
AU - Park, Young Shin
AU - Lim, Jaehoon
AU - Lee, Donggu
AU - Padilha, Lazaro A.
AU - McDaniel, Hunter
AU - Robel, Istvan
AU - Lee, Changhee
AU - Pietryga, Jeffrey M.
AU - Klimov, Victor I
PY - 2013
Y1 - 2013
N2 - Development of light-emitting diodes (LEDs) based on colloidal quantum dots is driven by attractive properties of these fluorophores such as spectrally narrow, tunable emission and facile processibility via solution-based methods. A current obstacle towards improved LED performance is an incomplete understanding of the roles of extrinsic factors, such as non-radiative recombination at surface defects, versus intrinsic processes, such as multicarrier Auger recombination or electron-hole separation due to applied electric field. Here we address this problem with studies that correlate the excited state dynamics of structurally engineered quantum dots with their emissive performance within LEDs. We find that because of significant charging of quantum dots with extra electrons, Auger recombination greatly impacts both LED efficiency and the onset of efficiency roll-off at high currents. Further, we demonstrate two specific approaches for mitigating this problem using heterostructured quantum dots, either by suppressing Auger decay through the introduction of an intermediate alloyed layer, or by using an additional shell that impedes electron transfer into the quantum dot to help balance electron and hole injection.
AB - Development of light-emitting diodes (LEDs) based on colloidal quantum dots is driven by attractive properties of these fluorophores such as spectrally narrow, tunable emission and facile processibility via solution-based methods. A current obstacle towards improved LED performance is an incomplete understanding of the roles of extrinsic factors, such as non-radiative recombination at surface defects, versus intrinsic processes, such as multicarrier Auger recombination or electron-hole separation due to applied electric field. Here we address this problem with studies that correlate the excited state dynamics of structurally engineered quantum dots with their emissive performance within LEDs. We find that because of significant charging of quantum dots with extra electrons, Auger recombination greatly impacts both LED efficiency and the onset of efficiency roll-off at high currents. Further, we demonstrate two specific approaches for mitigating this problem using heterostructured quantum dots, either by suppressing Auger decay through the introduction of an intermediate alloyed layer, or by using an additional shell that impedes electron transfer into the quantum dot to help balance electron and hole injection.
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U2 - 10.1038/ncomms3661
DO - 10.1038/ncomms3661
M3 - Article
VL - 4
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
M1 - 2661
ER -