Enhanced luminescence of Tb doping nanoscintillators based on NaLuF4 host matrix for X-ray imaging

Scintillators are of significance for X-ray excited luminescence (XEL) imaging from scientific research to medical diagnostics application. Rare earth fluoride nanocrystals possess distinctive luminescent properties originated from the abundant energy level of lanthanide activators, showing potential applications as next-generation scintillators. Herein, high Z atomic rare earth element lutetium was chosen to synthesized NaLuF4-based nanoscintillators by Tb doping. Core-shell structure was fabricated to further enhance the XEL emission intensity. The NaLuF4-based nanoscintillators was demonstrated more efficient XEL emission with 3-folds increase compared to NaYF4 nanocrystals. NaLuF4 nanocrystals with a 25 mol% Tb doping and an inert shell coating exhibited excellent scintillation performance with detection limit as low as to 57.05 nGyair s−1. X-ray imaging demonstrated a high spatial resolution of 10.5 lp mm−1 using a scintillator film made from as-prepared NaLuF4-based nanoscintillators. Finally, such NaLuF4-based scintillators film have been applied in X-ray imaging application for a chip and a biological specimen. This study proposed an effective strategy to enhance XEL for rare earth fluoride, providing the ability for high-quality X-ray imaging.