Stable and Efficient Pure-Red Perovskite Light-Emitting Diodes

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Bromine/iodine mixed halide perovskites are used for pure-red emission.
• Compositional heterogeneity and halide ion migration limit perovskite light-emitting diode (PeLED) performance and stability.

Purpose of the Study:

• To address compositional heterogeneity and halide ion migration in mixed halide perovskites.
• To enhance the efficiency and stability of pure-red PeLEDs.

Main Methods:

• Incorporation of multi-functional graphene quantum dots (GQDs) into perovskite materials.
• Investigating the role of GQDs in composition reconstruction, phase isolation, and halide ion immobilization.
• Analyzing the interactions between GQDs and perovskites, including coordination and hydrogen bonding.

Main Results:

• Achieved homogeneous perovskite films and suppressed halide ion migration.
• Demonstrated high-performance pure-red PeLEDs with 27.9% efficiency and narrow emission at 640 nm.
• Obtained a remarkable device lifetime of 110.3 hours with stable electroluminescence spectra.

Conclusions:

• Graphene quantum dots offer a synergistic role in stabilizing mixed-halide perovskites.
• This strategy provides an effective approach for developing stable and efficient pure-red PeLEDs.
• The findings contribute to overcoming critical challenges in mixed-halide perovskite applications.