AVS 57th International Symposium & Exhibition | |
Actinides and Rare Earths Topical Conference | Tuesday Sessions |
Session AC-TuA |
Session: | Science and Technology of Actinides and Rare Earths |
Presenter: | J. Choi, University of Florida |
Authors: | J. Choi, University of Florida T.-K. Tseng, University of Florida M.R. Davidson, University of Florida P.H. Holloway, University of Florida |
Correspondent: | Click to Email |
Scintillation detectors are commonly used for measuring radiation from nuclear materials. To date the scintillating material has been a single crystal, commonly doped with a rare earth ion that controls the wavelength and intensity of radioluminescence. Scintillating nanoparticles have the potential to replace the expensive, energy-intensive, limited volume single crystal detectors. In this study, scintillating Gd2SiO5:Ce3+ (GSO) nanoparticles with 5~10 nm diameters were prepared by a two-pot hot-solution growth (HSG at 200~300 oC) method. The Ce dopant concentration was varied between 0.2%~5% and concentration quenching was examined by photoluminescence (PL). Low (0.5% Ce) doped GSO nanoparticles exhibited good PL from both as-synthesized and calcined (1100˚C for 2 h in air) nanoparticles. Concentration quenching for nanoparticles occurred at higher Ce concentrations than for bulk samples; this will be discussed. The PL emission was from the 5d to two 4f levels (2T2 to 2F7/2 and 2F5/2 transitions) of Ce3+ at 420~450 nm. Photoluminescent excitation (PLE) spectra showed that the emission resulted from the direct excitation of the 4f–5d transition of Ce3+ excited between 270~375 nm. X-ray diffraction (XRD) and transmission electron microscopy (TEM) data showed that the GSO nanoparticles were amorphous as grown, but well crystallized after calcining. Quantum yield and radioluminescence data will be presented and discussed.