Metal–Organic Framework Based Thermoluminescence Dosimeter

Conventional thermoluminescence (TL) dosimeters, a type of off-line radiation detection device, are made of inorganic materials that usually require high synthesis temperatures (above 600 °C) and exhibit a multiple peak glow curve with an unclear structure–property relationship, posing an urgent need to seek new TL materials. Here, we presented the first case of applying metal–organic frameworks (MOFs) as a new material platform to construct a TL dosimeter. Synthesized at mild conditions (around 100 °C), the MOF-based TL material exhibits a single peak glow curve, high X-ray attenuation efficiency, and excellent dose–response linearity ranging from 0.01 to 10 Gy. The crystalline nature of MOFs associated with unambiguous structural information enables TL mechanism elucidation by theoretical calculations, which indicate that in SCU-300 the stable free radicals responsible for emitting visible light when heated are attributed to the charge transform (CT) from the anionic carboxyl groups to the centrosymmetric benzene ring. Furthermore, micron-sized SCU-300 single crystals were subjected to a point dose monitoring experiment based on a simulated eyeball model, and the measured doses match well (error <4%) with those by Monte Carlo calculations.