FSU Researchers Develop Novel Hybrid Materials for Advanced X-ray Detection

Researchers at Florida State University (FSU), led by Professor Biwu Ma, have developed new hybrid materials aimed at improving X-ray detection technologies. These innovations promise lower-cost and more adaptable solutions compared to current rigid, expensive, and energy-intensive inorganic detectors. The extensive research encompasses two distinct studies, showcasing capabilities in both direct X-ray detection and rapid-response scintillators.

These materials are designed to offer lower-cost and more adaptable solutions compared to current rigid, expensive, and energy-intensive inorganic detectors.

Research Overview

The FSU research focused on hybrid materials known as organic metal halide complexes (OMHCs) and organic metal halide hybrids (OMHHs). These materials uniquely combine organic and inorganic components, enabling their structures to be tailored at a molecular level for various forms of X-ray detection. X-ray technologies are critical across diverse fields, including medicine, security, and nuclear safety. Both studies received support from the National Science Foundation, with Oluwadara Joshua Olasupo and Tarannuma Ferdous Manny serving as lead authors.

Direct X-ray Detection Using OMHCs

One of the studies, published in the journal Small, introduced OMHCs specifically for direct X-ray detection. These materials are engineered to generate an electrical signal immediately upon exposure to X-rays.

• Material Composition: The particular OMHC compound utilized zinc, bromine, and a carbon-based molecule. This composition facilitates efficient X-ray absorption and robust electron transport within the material.

• Fabrication Process: A melt-processing method, reminiscent of plastic molding, was employed to transform OMHC molecular crystals into amorphous, glass-like materials. This approach stands in contrast to existing techniques that often rely on inorganic semiconductors, which can contain toxic elements and demand energy-intensive processing.

• Performance: Detectors fabricated from these innovative materials successfully converted X-rays into electrical signals, demonstrating strong responses even at low X-ray exposure levels. Tests further indicated that the detectors retained an impressive 98% of their initial performance after four months under ambient conditions.

  Detectors fabricated from these materials converted X-rays into electrical signals, demonstrating strong responses even at low X-ray exposure levels.

• Advantages: These OMHCs offer significantly lower production costs, as they can be synthesized from abundant and non-toxic raw materials. The melt-processing method also contributes to easier and more scalable device fabrication.

Scintillator Development Using OMHHs

The second study, featured in Angewandte Chemie, concentrated on an improved version of OMHH-based scintillators. These materials are characterized by their ability to emit strong visible light and respond rapidly when exposed to X-rays.

• Addressing Limitations: This advancement directly addresses previous limitations associated with OMHH scintillators, such which included slower crystal growth and light emission.

• Fast Response: Through meticulous molecular design, researchers successfully created an amorphous OMHH material that exhibits an exceptionally fast response time, measured in nanoseconds. The material's light emission primarily originates from its organic components, ensuring a faster response while maintaining strong X-ray absorption and high light output.

• Applications of Fast Scintillators: Fast-response scintillators are crucial for applications demanding clear images, enhanced timing accuracy, and reduced signal overlap, such as advanced medical imaging and high-speed security screening.

• Flexibility and Wearable Technology: The amorphous nature of this material allows for easy processing into thin films and coatings. This unique capability enabled the creation of fabric-based X-ray scintillators that can be integrated directly into clothing, potentially paving the way for wearable and portable radiation detection devices.

  This capability enabled the creation of fabric-based X-ray scintillators that can be integrated into clothing, potentially leading to wearable and portable radiation detection devices.

Future Prospects and Collaborations

Both studies leveraged similar material design strategies to effectively address pressing challenges in developing next-generation X-ray detection technologies. FSU has already initiated patent filings to facilitate the successful commercialization of these groundbreaking innovations. These advancements hold the potential to significantly benefit various fields, including medical imaging, security scanning, and nuclear safety.

The research group is actively engaged in collaborations with several esteemed institutions to explore diverse applications for these newly developed materials:

• Delft University of Technology for photon-counting computed tomography.
• University of Antwerp for luminescent dosimeters.
• University at Buffalo for pixelated X-ray imagers.
• Qrona Technologies for X-ray microscopy.