Lanthanide-based metal halides prepared at room temperature by recrystallization method for X-ray imaging

Area of Science:

• Materials Science
• Inorganic Chemistry
• Nanotechnology

Background:

• Lanthanide (Ln)-based metal halides are promising scintillators for X-ray imaging due to their luminescence, large Stokes shifts, and low toxicity.
• Current synthesis methods for these materials are often slow and require harsh conditions, limiting their practical application.
• Developing efficient and mild synthesis routes is crucial for advancing Ln-based scintillator technology.

Purpose of the Study:

• To establish a fast and mild synthesis method for lanthanide-based metal halides.
• To explore the potential of these synthesized materials as scintillators for X-ray imaging.
• To investigate the properties of a series of Cs3LnCl6 microcrystals.

Main Methods:

• A novel recrystallization method using methanol and ethanol as solvent and anti-solvent, respectively, was employed.
• The synthesis was conducted at room temperature, enabling mild and ultrafast preparation.
• The method allowed for large-scale production, recyclable recrystallization, and synthesis of high-entropy crystals.

Main Results:

• A series of Cs3LnCl6 (Ln = Ce to Lu) microcrystals were successfully synthesized at room temperature.
• Cs3TbCl6 microcrystals exhibited the highest photoluminescence quantum yield (90.8%) due to 4f→5d absorption.
• Under X-ray irradiation, Cs3TbCl6 demonstrated a high light yield (~51,800 photons MeV-1) and thin films achieved excellent spatial resolution (12 lp mm-1).

Conclusions:

• The developed recrystallization method offers an ultrafast and mild approach for synthesizing Ln-based metal halides.
• Cs3TbCl6 microcrystals show significant potential as high-performance scintillators for X-ray imaging.
• This work paves the way for the scalable production and application of advanced scintillator materials.