Enhanced Hole-Injecting Interface for High-Performance Deep-Blue Perovskite Light-Emitting Diodes Using...

Area of Science:

• Materials Science
• Optoelectronics
• Chemistry

Background:

• Deep-blue perovskite light-emitting diodes (PeLEDs) are crucial for Rec. 2020 compliant displays but suffer from low efficiency and stability.
• Mixed-halide perovskites used for blue emission degrade rapidly under bias due to halide migration and vacancy formation.

Purpose of the Study:

• To develop high-performance deep-blue PeLEDs with improved brightness, quantum efficiency, and operational stability.
• To address the degradation issues in wide-bandgap perovskites for stable deep-blue emission.

Main Methods:

• Engineered a self-assembled monolayer (SAM) molecule, Br-2ETP, with a high dipole moment to tune interface properties.
• Utilized the Br-2EPT interface to optimize energy level alignment and suppress charge recombination.
• Investigated the effect of Br-2EPT on perovskite film morphology.

Main Results:

• Achieved deep-blue electroluminescence at 457 nm.
• Demonstrated a high external quantum efficiency of 6.56%.
• Observed enhanced spectral and operational stabilities in the fabricated PeLEDs.

Conclusions:

• Br-2ETP effectively improves hole injection and carrier balance, leading to high-efficiency deep-blue emission.
• The engineered interface enhances perovskite film quality and device stability.
• This work presents a viable strategy for realizing stable and efficient deep-blue PeLEDs for display applications.