The inserted dipole layer enables highly powerful blue perovskite quantum dot-based light-emitting diodes

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Blue perovskite light-emitting diodes (LEDs) show high external quantum efficiencies (EQEs) but limited power efficiency (PE).
• Power efficiency is crucial for quantifying electricity consumption in LEDs.
• Improving PE is essential for developing practical perovskite lighting.

Purpose of the Study:

• To enhance the power efficiency (PE) of blue perovskite LEDs.
• To suppress non-radiative losses and improve charge injection using polymer dipoles.
• To achieve record performance metrics for blue perovskite LEDs.

Main Methods:

• Incorporation of poly(1,1-difluoroethylene) (PVDF) polymer dipoles into the CsPbCl3-xBrx quantum dot (QD) layer.
• Utilizing the ordered dipolar structure of PVDF to regulate electron and hole injection.
• Leveraging polar atoms (F, H) in PVDF to interact with QD surfaces and suppress trap-assisted non-radiative recombination.

Main Results:

• Achieved a record power efficiency (PE) of 43.9 lm W⁻¹.
• Attained a record external quantum efficiency (EQE) of 28.7%.
• Demonstrated a low turn-on voltage of 2.2 V and maximum luminance of 5474 cd m⁻².

Conclusions:

• PVDF polymer dipoles effectively regulate charge injection and suppress non-radiative losses in blue perovskite LEDs.
• The developed perovskite LEDs offer significant improvements in energy efficiency.
• These findings pave the way for energy-conserving perovskite lighting applications.