Lead-free organic-inorganic hybrid scintillators for X-ray detection

Scintillators, which can convert high-energy particles (X-rays) into detectable low-energy ultraviolet-visible-near-infrared photons, are essential components of X-ray detectors and show extensive practical applications in nondestructive detection and medical imaging. Traditionally, inorganic scintillators represented by CsI:Tl have achieved definite progress. However, the harsh preparation conditions, high production cost, and poor mechanical properties impede their potential development in the high-end X-ray imaging field. Organic-inorganic hybrid metal complexes could be excellent alternatives, by virtue of their structural and spectral tunability, good solution processability, and excellent photophysical properties. This review mainly focuses on eco-friendly lead-free metal (Mn2+, Cu+, Sb3+, Sn2+, Ge2+, Ln3+, etc.) complex scintillators. The luminescence mechanisms are introduced and the scintillation performance, such as light yield, limit of detection, imaging resolution, etc., is highlighted. Moreover, the current challenges and perspectives in this emerging field are described. It is hoped to provide some theoretical guidance for the continuous development of the new scintillator systems. Scintillators can convert high-energy incident X-rays into detectable low-energy ultraviolet-visible-near-infrared photons. This review mainly focuses on lead-free organic-inorganic hybrid metal (Mn2+, Cu+, Sb3+, Ln3+, etc.) complex scintillators. The luminescence mechanisms are introduced and the scintillation performance, such as light yield, limit of detection, imaging resolution, etc., is highlighted Finally, the current challenges and perspectives in this emerging field are described.image