Perovskite light-emitting diodes based on spontaneously formed submicrometre-scale structures

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Light-emitting diodes (LEDs) are crucial for modern technology but limited by nonradiative recombination and light trapping.
• Existing light extraction methods for planar LEDs often involve complex fabrication and can negatively impact spectral and directional properties.

Purpose of the Study:

• To demonstrate efficient and high-brightness electroluminescence from solution-processed perovskites.
• To develop a simpler method for light extraction in LEDs that avoids complex fabrication and preserves light properties.

Main Methods:

• Introducing amino-acid additives into perovskite precursor solutions to induce spontaneous submicrometre-scale structure formation.
• Utilizing these self-formed structures for efficient light extraction.
• Employing additives for passivation of perovskite surface defects and reduction of nonradiative recombination.

Main Results:

• Achieved efficient and high-brightness electroluminescence with wavelength- and viewing-angle-independent output.
• Demonstrated peak external quantum efficiency of 20.7% and energy-conversion efficiency of 12% at high current density.
• Showcased performance approaching that of leading organic LEDs.

Conclusions:

• Solution-processed perovskites with self-formed submicrometre structures offer a promising route to highly efficient LEDs.
• Amino-acid additives provide a simple yet effective method for enhancing light extraction and passivating defects.
• This approach represents a significant advancement in LED technology, potentially rivaling organic LEDs.