Radiation-induced changes in the photoluminescence properties of NaMgF3:Yb nanoparticles: Yb3+ → Yb2+ valence conversion and oxygen-impurity charge transfer

Strained cuboid Yb-doped NaMgF3 nanoparticles were synthesised via a hydrothermal synthesis technique. The morphologies and crystal phases of the nanoparticles were the same for two different Yb concentrations (0.1% and 1%). Prior to X-ray exposure, photoluminescence was observed from O2- impurities, Yb3+, and Yb2+. The infrared Yb3+ luminescence could be excited using ultraviolet stimulation via an O2- -> Yb3+ charge transfer process that also sensitised the emission. After X-ray exposure the intensity of the Yb2+ luminescence increased due to the radiation-induced conversion Yb3+ -> Yb2+, indicating that Yb3+ acted as an electron trap. This radiophotoluminescence effect could find applications in radiation dose detection and monitoring, where the intensity of the Yb2+ emissions are proportional to the absorbed dose.

Automated summary

Strained cuboid Yb-doped NaMgF3 nanoparticles were synthesized using a hydrothermal synthesis technique, showing consistent morphologies and crystal phases for different Yb concentrations. Photoluminescence was observed from O2- impurities, Yb3+, and Yb2+ before X-ray exposure, with Yb3+ luminescence being excited by ultraviolet stimulation through a charge transfer process. After X-ray exposure, the Yb2+ luminescence intensity increased due to the conversion of Yb3+ to Yb2+ by radiation, suggesting the potential application of this radiophotoluminescence effect in radiation dose detection and monitoring.