Multivariant ligands stabilize anionic solvent-oriented α-CsPbX₃ nanocrystals at room temperature.

Area of Science:

• Materials Science
• Nanotechnology
• Solid State Chemistry

Background:

• Cubic phase CsPbX₃ nanocrystals (NCs) show promise for optoelectronics.
• Their application is limited by poor chemical stability due to dynamic ionic surfaces.

Purpose of the Study:

• Develop a protocol for high-quality α-CsPbX₃ NCs under ambient conditions.
• Achieve tunable optical properties and enhanced stability.

Main Methods:

• Synthesized CsPbX₃ NCs by controlling ligand-solvent interactions.
• Tuned NC size and optical properties by altering cationic ligands and reaction solvents (e.g., CH₃Cl, CH₂Cl₂, toluene).
• Eliminated traditional solvents (ODE, DMSO, DMF) to prevent ligand loss and phase transitions.

Main Results:

• Achieved large-scale synthesis of cubic CsPbI₃ NCs, overcoming room-temperature phase transition challenges.
• Synthesized ultrasmall CsPbCl₃ NCs emitting at 385 nm for the first time.
• Demonstrated near-perfect photoluminescence quantum yield (PL QY) and long-term stability in moisture.

Conclusions:

• The developed protocol yields stable, high-performance CsPbX₃ NCs.
• Ligand passivation remains effective, preserving NC quality.
• The method offers a pathway for advanced optoelectronic device development.