Newswise — In medicine, security, nuclear safety and scientific research, X-rays are essential tools for seeing what remains hidden.

The materials used to create X-ray detectors can be rigid, expensive and laborious to produce. But new research led by FSU Department of Chemistry and Biochemistry Professor Biwu Ma is creating lower-cost, adaptable materials that could revolutionize X-ray detection technologies.

In two separate research studies, Ma’s group offers solutions to long-standing challenges in X-ray imaging. In the first study, published in Small, the team developed a new material that generates electric signals when exposed to X-rays, enabling direct X-ray detection. In the second study, published in Angewandte Chemie, the researchers used a related material to produce low-cost scintillators, which are materials that emit visible light when exposed to X-rays or other high-energy radiation.

“We have traditionally relied on inorganic materials for X-ray detection, but they are often rigid, expensive to manufacture and energy-intensive to produce, and they have many limitations,” Ma said. “What we have been trying to develop is a new class of materials that can address the issues and challenges faced by existing materials.”

In these studies, researchers created new hybrid materials composed of both organic and inorganic components, known as organic metal halide complexes (OMHCs) and organic metal halide hybrids (OMHHs). By tailoring the structures of these materials at the molecular level, the team enabled different forms of X-ray detection. This research represents a major step toward developing lower-cost, scalable and flexible X-ray detector technologies capable of overcoming key limitations of conventional inorganic systems.

Glassy OMHC films for direct X-ray detectors

Commercially available direct X-ray detectors are constructed using inorganic semiconductors, made from non-carbon materials, such as cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe). These materials contain toxic elements and require energy-intensive processing, making them expensive.

In the first study, the team demonstrated, for the first time, the use of OMHCs as a material for making direct X-ray detectors. These are materials composed of carbon-based semiconducting molecules that are bonded to metal halides, which are compounds made of metal and a halogen element. The specific OMHC compound developed by the team was created out of zinc, bromine, and a carbon-based molecule, enabling efficient X-ray absorption and electron transport within a single material.

Using a melt-processing approach, similar to melting plastics and allowing them to cool into a desired shape, the researchers transformed OMHC molecular crystals into amorphous, glass-like materials that can be molded into ready-to-use forms. They used these materials to make direct X-ray detectors that convert incoming X-rays into electrical signals.

Results

The resulting detectors produced strong electrical responses even at low X-ray exposure levels, making them more effective than detectors made from traditional materials. The team also evaluated the long-term stability of detectors made with the new material. After storing the detectors for four months under ambient conditions, testing showed they retained 98% of their initial performance.

OMHCs offer additional practical advantages. They are less expensive to produce than materials currently used in commercially available X-ray detectors because they can be synthesized from abundant and non-toxic raw materials. Moreover, the simple melt-processing method also makes device fabrication easier and more scalable than existing approaches.

“This is actually the first time these OMHC materials have been used to fabricate direct X-ray detectors,” said Ma. “They can be prepared in a low-cost way while delivering high performance. From a sustainability perspective, this new class of materials offer tremendous advantages over conventional materials.”

Bright, fast and flexible scintillators: X-ray components on fabric

In the second study, the team developed a new version of OMHH-based scintillators that exhibit high light yield and fast response, meaning they emit strong visible light and respond almost instantly when exposed to X-rays. OMHHs are similar to OMHCs, but a different type of chemical bond brings together organic components and metal halides into a single material.

The work builds on the team’s years of effort in the area since 2020, when they demonstrated the first ecofriendly OMHH scintillators. Earlier versions of OMHH scintillators relied on slow crystal growth processes that limited their size and flexibility, and their light emission faded relatively slowly. This latest generation of OMHH scintillators overcomes both challenges by eliminating the need for crystal growth and by dramatically speeding up the light response.

Results

By carefully designing the molecular structure, the team created a new amorphous OMHH material that shows fast response in nanoseconds. Unlike earlier versions of OMHH scintillators, in which light emission comes from metal halide centers and lingers for longer periods, the new material emits from the organic components of the material, exhibiting a faster response while maintaining excellent X-ray absorption and high light output.

Fast-response scintillators are especially important for advanced radiation detection and imaging. Their rapid light emission allows for clearer images, improved timing accuracy and reduced signal overlap, which are critical for applications such as medical imaging, security screening and real-time radiation monitoring.

The amorphous nature of the material also allows it to be easily processed into thin films and coatings. Using this approach, the team created fabric-based X-ray scintillators that can be integrated into clothing, enabling wearable and portable radiation detectors. These flexible scintillating fabrics represent a significant departure from traditional rigid detectors and open new possibilities for comfortable, adaptable and low-cost X-ray detection technologies.

Why it matters

While the two studies focused on different X-ray detection approaches, both used similar material design strategies to address major challenges in developing next-generation X-ray detection technologies.

FSU has begun filing patents to commercialize the technologies developed in Ma’s group and test them in real-world conditions. These advancements offer exciting and cost-effective solutions for next-generation X-ray detection technologies. Commercialization of these materials could benefit many fields, including medical imaging, security scanning, nuclear safety and more.

In addition to the team’s internal efforts, the group has collaborated with research institutions and industrial partners to explore diverse applications of these materials. These collaborations include Delft University of Technology (TU Delft) for photon-counting computed tomography, the University of Antwerp for luminescent dosimeters for radiotherapy, the University at Buffalo for pixelated X-ray imagers, and Qrona Technologies for X-ray microscopy technologies.

“The materials are very unique and were developed here at FSU,” Ma said. “We believe our materials and devices have tremendous potential to outperform existing technologies and address key challenges in the field.”

The research has been supported by federal funding from the National Science Foundation Division of Materials Research and Innovation and Technology Ecosystems. The lead authors of the two publications are Oluwadara Joshua Olasupo, who recently graduated with a Ph.D., and Tarannuma Ferdous Manny, a fourth-year graduate student. Collaborators from TU Delft and the University at Buffalo also contributed to the work. The research additionally involved high school students through the FSU Young Scholars Program.

Newswise — Researchers at Lawrence Livermore National Laboratory (LLNL) have co-developed a new way to precisely control the internal structure of common plastics during 3D printing, allowing a single printed object to seamlessly shift from rigid to flexible using only light.

In a paper published today in Science, the researchers describe a technique called crystallinity regulation in additive fabrication of thermoplastics (CRAFT) that enables microscopic control over how plastic molecules arrange themselves as an object is printed. The work opens new possibilities for advanced manufacturing, soft robotics, national defense, energy damping and information storage, according to the researchers. The team includes collaborators from Sandia National Laboratories (SNL), the University of Texas at Austin, Oregon State University, Arizona State University and Savannah River National Laboratory.

The team demonstrated that by carefully tuning light intensity during printing, they could dictate how crystalline or amorphous a thermoplastic becomes at specific locations within a part. That molecular arrangement determines whether a material behaves more stiff and rigid, or as a softer, more flexible plastic — without changing the base material. CRAFT builds on that principle by allowing researchers to control crystallinity spatially during printing, rather than uniformly throughout a part.

“A classic example of crystallinity is the difference between high-density polyethylene —picture a milk jug — and low-density polyethylene, like squeeze bottles and plastic bags. The bulk property difference in these two forms of polyethylene stems largely from differences in crystallinity,” said LLNL staff scientist Johanna Schwartz. “Our CRAFT effort is exciting in that we are controlling the crystallinity within a thermoplastic spatially with variations in light intensity, making areas of increased and decreased crystallinity to produce parts with control over material properties throughout the whole geometry.”

A key challenge, however, was translating this new materials capability into practical manufacturing instructions that could be used on real 3D printers, according to LLNL engineer Hernán Villanueva. Villanueva joined the project after early discussions with Schwartz and former SNL scientists Samuel Leguizamon and Alex Commisso identified a missing link: a way to convert any three-dimensional computer-aided design (CAD) into the detailed light patterns needed to print parts using the CRAFT method.

Villanueva said he drew on prior work in a multi-institutional team focused on lattice structures and advanced manufacturing workflows. In that effort, he developed software that rapidly converted complex, topology-optimized designs into printing instructions by parallelizing the process on LLNL’s high-performance computing (HPC) systems — reducing turnaround times from days to hours or minutes.

Applying that same computational approach to CRAFT, Villanueva adapted the workflow to encode “changes in light” rather than changes in material. He was soon able to convert 3D CAD geometries directly into CRAFT printing instructions, cutting instruction-generation time from hours — or even a full day — down to seconds, making rapid design iteration and demonstration of the method practical.

“This work is a natural extension of the Lab’s strengths in advanced manufacturing and materials by design,” Villanueva said. “As part of the CRAFT effort, we have evolved a tool that connects materials science with computational workflows and advanced printing, enabling us to move directly from a 3D design to a part with spatially varying properties.”

The team’s method relies on a light-activated polymerization process in which exposure level governs the stereochemistry of growing polymer chains, researchers said. Lower light intensities favor more ordered crystalline regions, while higher intensities suppress crystallization, yielding softer, more transparent material. By projecting grayscale patterns during printing, the team produced parts with smoothly varying mechanical and optical properties.

The demonstrated ability to tune properties by changing a light’s intensity rather than swapping materials could significantly simplify additive manufacturing (3D printing), Schwartz explained.

“If you can get many different properties from one vat of material, printing complex multi-material or multi-modulus structures becomes much easier,” she said.

The researchers demonstrated the CRAFT technique on commercial 3D printers, fabricating objects that combine multiple mechanical behaviors in a single print. Examples included bio-inspired structures that mimic bones, tendons and soft tissue, reproductions of famous paintings, as well as materials designed to absorb or redirect vibrational energy without adding weight or complexity. Among the most striking demonstrations was the ability to encode crystallinity through transparency differences, according to Schwartz.

“Being able to visualize the differences easily spatially, to the point of generating the Mona Lisa out of only one material, was incredibly cool,” Schwartz said.

LLNL’s Villanueva said the work reflects the Lab’s long-standing investments in HPC and in integrating modeling, design tools and novel manufacturing processes. He added that future work could integrate topology optimization directly into the CRAFT framework, enabling researchers to optimize light patterns themselves — rather than material layouts — to achieve desired performance.

Because the process works with thermoplastics — materials that can be melted and reshaped — printed parts remain recyclable and reprocessable, an important advantage for manufacturing sustainability. The findings suggest a future where 3D-printed plastic components can be tailored at the molecular level for specific functions, bridging the gap between material science and digital manufacturing.

From an applications standpoint, Schwartz said the technology could have broad and near-term impact.

“Energy dampening and metamaterial design are the most exciting use cases to me,” she said. “From space to fusion to electronics, there are so many industries that rely on energy and vibrational dampening control. This CRAFT printing process can access all of them.”