Supersaturated Antisolvent-Assisted Crystallization for Highly Efficient Inorganic Perovskite Light-Emitting Diodes

Area of Science:

• Materials Science
• Solid-State Chemistry
• Optoelectronics

Background:

• Cesium lead bromide (CsPbBr3) perovskite films are crucial for optoelectronic applications due to their luminescence properties.
• Controlling nanocrystal size is key to optimizing film quality and device performance.
• Existing methods often struggle to achieve both high luminescence and stability simultaneously.

Purpose of the Study:

• To develop a novel strategy for fabricating nanocrystalline CsPbBr3 perovskite films with improved luminescence and stability.
• To investigate the role of a supersaturated antisolvent in controlling perovskite crystal growth.
• To enhance the performance and operational lifetime of CsPbBr3-based perovskite light-emitting diodes (PeLEDs).

Main Methods:

• Antisolvent-assisted crystallization process utilizing a CsBr supersaturated antisolvent.
• Inhibition of perovskite crystal growth through controlled precipitation of CsBr.
• Characterization of nanocrystalline film morphology, photoluminescence, and device performance.

Main Results:

• Achieved nanocrystalline CsPbBr3 films with an average grain size of approximately 39 nm, a 41% reduction compared to control samples.
• Demonstrated significantly enhanced photoluminescence quantum yield in the perovskite thin films.
• Developed CsPbBr3 perovskite light-emitting diodes (PeLEDs) with doubled performance metrics (CEmax of 94.64 cd A-1, EQEmax of 22.93%) and improved operational stability.

Conclusions:

• The supersaturated antisolvent strategy effectively inhibits crystal growth, leading to smaller nanocrystalline grains.
• This method enhances the optoelectronic properties and device performance of CsPbBr3 perovskite films.
• The incorporation of CsBr additives offers multifunctional benefits, including reduced leakage current and extended device lifetime.