Dual Passivation Strategy for Highly Stable Blue-Luminescent CsPbBr₃ Nanoplatelets

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Colloidal cesium lead halide (CsPbX3) perovskite nanocrystals are promising for optoelectronics.
• Their practical use is limited by poor stability and low photoluminescence efficiency.

Purpose of the Study:

• To develop highly stable blue-emitting CsPbBr3 nanoplatelets with improved photoluminescence.
• To investigate the role of zirconium acetylacetonate in controlling morphology and enhancing stability.

Main Methods:

• Fabrication of CsPbBr3 nanoplatelets using zirconium acetylacetonate [Zr(acac)4] for morphology regulation and dual surface passivation.
• Tuning nanocrystal morphology (nanocubes, nanoplatelets, nanorods) and emission color (green to dark blue) by adjusting Zr(acac)4 content.
• Characterization of optical properties, including photoluminescence quantum yield and emission wavelength.

Main Results:

• Achieved adjustable light emission from green to dark blue and controllable morphology.
• Optimized nanoplatelets exhibited bright blue emission (459 nm) with a high photoluminescence quantum yield of 90%.
• Zr(acac)4 incorporation led to oriented growth, surface defect repair, and formation of a Zr(OH)4 cluster capping layer, significantly enhancing stability.

Conclusions:

• Zirconium acetylacetonate is an effective additive for fabricating highly stable, efficient blue-emitting CsPbBr3 perovskite nanocrystals.
• The dual passivation strategy overcomes key limitations, enabling potential applications in advanced blue-emitting optoelectronic devices.