High-Efficiency Perovskite Quantum-Dot Light-Emitting Devices by Effective Washing Process and Interfacial Energy...

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• All inorganic perovskite quantum dots (PeQDs) are promising for displays and lighting due to their optical properties and processability.
• High photoluminescence quantum yields (PLQYs) and narrow emission are key for efficient light-emitting devices (LEDs).

Purpose of the Study:

• To fabricate low-driving-voltage and high-efficiency CsPbBr3 PeQD-LEDs.
• To improve PeQD film quality and device performance by removing excess ligands.

Main Methods:

• A PeQDs washing process using butyl acetate (AcOBu) was employed to remove excess ligands from CsPbBr3 PeQDs.
• Energy level alignment was optimized for effective hole injection into the PeQDs.

Main Results:

• The AcOBu-washed CsPbBr3 PeQDs film showed a high PLQY of 42% and narrow emission (19 nm FWHM).
• The fabricated PeQD-LED achieved a maximum power efficiency of 31.7 lm W⁻¹ and external quantum efficiency (EQE) of 8.73%.

Conclusions:

• Ligand removal and energy level alignment are effective strategies for enhancing PeQD film PLQY and device efficiency.
• This approach shows promise for advanced thin film display and solid-state lighting applications.