Optimization of the Synthesis and Physical Characterization ofPraseodymium-Doped Type III KGd(PO3)4 Nanocrystals

摘要

Scintillator materials are used as detectors in the ray imagingtechniques for medical diagnosis. Because the ideal medical scintillator materialdoes not exist, many efforts are being made to find new materials that satisfy agreater number of properties. Here, the synthesis conditions of Pr:KGd(PO3)4nanocrystals by the modified Pechini method are optimized to obtain a singlecrystalline phase of those that form the polymorphism of KGd(PO3)4. Theinterest lies in the type III phase because less quenching by Pr3+ concentration isexpected. By performing transmittance measurements and because of the widetransparency window of the type III KGd(PO3)4 host, the 3H4 → 5d1 absorptiontransition of Pr3+ has been observed in the vacuum ultraviolet spectral range. Aftercreating electron?hole pairs in the host due to the excitation of the material by Xray radiation, the bands corresponding to the 5d1 → 3H4, 3H5, 3H6 and 5d1 → 3F3,3F4,1G4 transitions of Pr3+ have been observed in the near-visible spectral range,being these 5d → 4f transitions interesting for scintillation applications. Therefore, the type III Pr:KGd(PO3)4 nanocrystalsallow the conversion from high-energy radiation to visible or near-visible light.