Multifunctional Additives With Dual Anions and Alkali Metal Cation for Efficient Perovskite Light-Emitting Diodes

Area of Science:

• Materials Science
• Optoelectronics
• Chemistry

Background:

• Quasi-2D perovskites show promise for high-performance perovskite light-emitting diodes (PeLEDs) due to their color purity and quantum yield.
• Current green PeLED performance is hindered by defects and low-n phases in perovskite films, leading to poor carrier mobility and recombination.

Purpose of the Study:

• To enhance the quality and performance of quasi-2D perovskite films for green PeLEDs.
• To investigate the role of biocompatible salicylates as a tri-functional additive strategy.

Main Methods:

• Incorporation of sodium salicylate (NaSA) and potassium salicylate (KSA) into quasi-2D perovskite materials.
• Passivation of lead (Pb) defects via C═O coordination and suppression of low-n phases through ─OH group interaction.
• Regulation of crystallization and promotion of radiative recombination using alkali metal ions (Na+, K+).

Main Results:

• The tri-functional additive strategy successfully produced high-quality quasi-2D perovskite films.
• Green PeLEDs with NaSA additive achieved a maximum external quantum efficiency (EQE) of 22.06% at 527 nm.
• A maximum luminance of 36785 cd/m² was recorded, demonstrating significant performance enhancement.

Conclusions:

• Salicylates act as multifunctional additives, passivating defects and optimizing phase composition in perovskites.
• The strategy effectively enhances carrier mobility and radiative recombination, leading to improved PeLED performance.
• This work offers valuable insights into using multifunctional additives for advanced electroluminescent devices.