Minimizing heat generation in quantum dot light-emitting diodes by increasing quasi-Fermi-level splitting
Source abstract
Abstract
Minimizing heat accumulation is essential to prolonging the operational lifetime of quantum dot light-emitting diodes (QD-LEDs). Reducing heat generation at the source is the ideal solution, which requires high brightness and quantum efficiency at low driving voltages. Here we propose to enhance the brightness of QD-LEDs at low driving voltages by using a monolayer of large QDs to reduce the packing number in the emitting layer. This strategy allows us to achieve a higher charge population per QD for a given number of charges without charge leakage, enabling enhanced quasi-Fermi-level splitting and brightness at low driving voltage. Due to the minimized heat generation, these LEDs show a high power conversion efficiency of 23% and a T95 operation lifetime (the time for the luminance to decrease to 95% of the initial value) of more than 48,000 h at 1,000 cd m-2.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Quantum Dots Synthesis And Properties · Semiconductor Quantum Structures and Devices · Chalcogenide Semiconductor Thin Films
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (31)
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