Dual-Hydrogen-Bonded Interfaces Unlock Record-High Efficiency and Stability in Eco-friendly Copper-Iodide Deep-Blue...

Area of Science:

• Materials Science
• Optoelectronics
• Sustainable Technology

Background:

• Deep-blue light-emitting diodes (LEDs) are crucial for advanced displays but face challenges in efficiency and operational stability.
• Eco-friendly and high-performance deep-blue emitters are critical for next-generation display technologies.

Purpose of the Study:

• To develop highly efficient and stable eco-friendly deep-blue LEDs.
• To address the bottleneck of interfacial defects and charge transport in metal halide emitters.

Main Methods:

• Utilized a copper-iodide hybrid emitter for deep-blue light emission.
• Implemented dual interfacial hydrogen-bond passivation by sandwiching the emissive layer between a self-assembled monolayer and a poly(methyl methacrylate) layer.
• Optimized device architecture to passivate defects, improve hole injection, and control electron transport.

Main Results:

• Achieved a record 12.57% external quantum efficiency and 3,970 cd m⁻² luminance.
• Demonstrated a 204-hour half-lifetime at 100 cd m⁻², an 85-fold improvement over perovskite counterparts.
• Successfully passivated interfacial defects and balanced charge injection/transport.

Conclusions:

• The dual interfacial hydrogen-bond passivation strategy offers a viable pathway for high-performance, stable, and sustainable deep-blue LEDs.
• This work sets a new benchmark for metal halide deep-blue LEDs and provides a design principle for future display technologies.