Boron Cluster-Based X-Ray Scintillators for Highly Efficient Radioluminescence

Area of Science:

• Materials Science
• Chemistry
• Physics

Background:

• Organic scintillators offer potential but suffer from poor x-ray absorption and exciton utilization.
• Existing scintillators often have limitations in performance for practical x-ray detection applications.

Purpose of the Study:

• To design and synthesize novel, highly efficient boron cluster-based organic scintillators.
• To overcome the limitations of conventional scintillators for improved x-ray detection.

Main Methods:

• Synthesized organic scintillators with a donor-acceptor architecture using carbazole and iodophenyl carborane clusters.
• Evaluated scintillation performance, including absolute quantum yields and x-ray detection limits.
• Conducted mechanistic studies to understand the origin of radioluminescence and exciton utilization.

Main Results:

• Achieved high absolute quantum yields up to 95.8%.
• Demonstrated an ultralow x-ray detection limit of 76 nGy s⁻¹.
• Observed efficient intramolecular charge transfer leading to thermally activated delayed fluorescence (TADF) and near-100% exciton utilization.

Conclusions:

• Metal-free boron clusters are effective building blocks for high-performance organic scintillators.
• The developed materials show exceptional scintillation performance, surpassing commercial inorganic BGO scintillators.
• This research opens new possibilities for next-generation x-ray scintillators.