X-rays play a crucial role in both medical diagnostics and industrial applications, ranging from dental checkups to airport baggage screenings. However, these high-energy rays can emit ionizing radiation, which may pose risks with excessive or long-term exposure. Researchers have now made strides towards safer X-ray use by developing a highly sensitive, foldable detector that can produce high-quality images while using lower doses of radiation.
X-rays play a crucial role in both medical diagnostics and industrial applications, ranging from dental checkups to airport baggage screenings. However, these high-energy rays can emit ionizing radiation, which may pose risks with excessive or long-term exposure. Researchers have now made strides towards safer X-ray use by developing a highly sensitive, foldable detector that can produce high-quality images while using lower doses of radiation.
According to Omar F. Mohammed, the lead author of this study published in ACS Central Science, “This development lowers detection thresholds and opens the door to safer and more energy-efficient practices in medical imaging and industrial monitoring. It shows that cascade-engineered devices can enhance the performance of single crystals in X-ray detection.”
X-rays are a type of electromagnetic radiation, similar to visible light and radio waves. Their high energy allows them to penetrate many materials, including the soft tissues in our bodies. When an X-ray image, called a radiograph, is taken, the rays can either pass through the body, resulting in shadowy outlines, or be absorbed by denser tissues like bones, which appear as brighter spots. While the radiation exposure during a single scan is considered safe, repeated scans can accumulate exposure and could potentially be harmful. This makes it critical to use fewer rays during each scan, when possible.
However, using fewer rays typically results in a lower-quality radiograph. To tackle this issue, a team led by Omar Mohammed at the King Abdullah University of Science and Technology focused on enhancing the sensitivity of the detector, allowing for high-quality X-rays at lower doses.
To improve the X-ray detector’s sensitivity, the researchers targeted the reduction of dark current—background noise generated by the device. They engineered detectors from specific methylammonium lead bromide perovskite crystals and arranged them in a cascade electrical configuration.
This innovative cascade design nearly cut the dark current in half, enhancing the X-ray detection limit fivefold compared to earlier detectors made from the same materials but lacking the cascade structure. The radiographs captured with the new detector were able to display intricate details, such as a metal needle piercing a raspberry and the internal parts of a USB cable. The researchers believe this technology holds great potential for creating foldable, sensitive, and safer commercial X-ray devices, which would reduce radiation exposure during medical procedures and effectively monitor subtle changes in industrial settings.
The authors acknowledge financial support from the King Abdullah University of Science and Technology (KAUST).
