Rational design and synthesis of scintillating lanthanide coordination polymers for highly efficient X-ray imaging

Scintillators with high X-ray imaging performance are highly desirable. Traditional inorganic scintillators are restricted by the rigorous preparation conditions and easy deliquescence, while organic scintillators suffered from a low X-ray absorption coefficient and low energy resolution. Metal–organic scintillators were developed to overcome the above-mentioned disadvantages, but they were still limited by the inherent low X-ray attenuation performance of organic ligands and the low energy transfer efficiency between the absorption center and the luminescent center. In this work, two one-dimensional linear lanthanide-based scintillating metal–organic coordination polymers (CPs) were developed by a simple and controllable one-step solvothermal method. High-Z lanthanide atoms could efficiently transform the high-energy X-ray to characteristic visible light via the energy bridge effect of organic ligands, which improved the conversion efficiency to enhance light emission. To evaluate the X-ray imaging performance, scintillating CPs were prepared into thin films, which exhibited relatively high spatial resolution. Considering the good X-ray irradiation stability and humidity stability, the lanthanide scintillating CPs are believed to be very promising materials for X-ray imaging.