Single crystal solar material outperforms commercial x-ray detectors

A re-engineered solar cell material can detect x-rays at doses 250 times less than the current top-performing detectors. High-quality single crystals of bismuth oxyiodide (BiOI) demonstrated enhanced x-ray attenuation properties, so patients going for an x-ray might one day benefit from reduced radiation exposure making this essential medical procedure safer.

X-rays are a valuable diagnostic tool but prolonged or repeated exposure to this ionising radiation can increase the risk of cancer. Radiation doses are currently determined by the properties of attenuation materials in the detector which absorb the x-rays passed through the sample to create an image. ‘A semiconductor x-ray sensing material needs to have a high effective atomic number (Z number) to sufficiently stop high energy photons like x-rays,’ explains Wanyi Nie, an optoelectronics researcher at Los Alamos National Laboratory, US. ‘It should also have good charge conduction properties to accurately measure the radiation intensity, especially under low dose conditions.’