Efficient lead-free antimony halide light-emitting diodes with 22% external quantum efficiency via a binary...

Area of Science:

• Materials Science
• Solid-State Physics
• Optoelectronics

Background:

• Lead halide emitters are promising for LEDs but face toxicity concerns.
• Developing efficient and lead-free alternatives is crucial for commercialization.

Purpose of the Study:

• To report solution-processed lead-free antimony halide-based LEDs.
• To investigate the mechanism of efficient emission in these novel materials.

Main Methods:

• Fabrication of LEDs using a binary host-guest architecture with a zero-dimensional organic-inorganic antimony(III) halide.
• Optical and photophysical studies, including photoluminescence quantum yield measurements.
• Theoretical calculations to elucidate emission mechanisms.
• Doping with (AylPPh3)2SbCl5 to optimize film morphology and charge transport.

Main Results:

• Achieved external quantum efficiency of 22% and current efficiency of 55.84 candelas per ampere.
• Demonstrated bright emission with near-unity photoluminescence quantum yield.
• Identified self-trapped exciton emission as the underlying mechanism for high efficiency.
• Doping improved film morphology, charge carrier mobility, and carrier balance, leading to superior device performance.

Conclusions:

• Solution-processed lead-free antimony halide-based LEDs show exceptional performance.
• The binary host-guest architecture and self-trapped exciton emission are key to high efficiency.
• These findings pave the way for safer, high-performance lighting technologies.