0000000000866466
AUTHOR
Cecilia Mortalò
Effect of hydrothermal time on the forming specific morphology of YPO4:Eu3+ nanoparticles for dedicated luminescent applications as optical markers
A way to control the desired shape and microstructure of YPO4:Eu3+ nanoparticles through the precipitation method followed by a hydrothermal treatment is reported. This method is useful for achieving very high control over the YPO4:Eu3+ formation process with the selection of appropriate synthesis parameters. In detail, the autoclave processing time allows control of the shape and size of nano-needle-shaped particles independently in both directions, as confirmed by X-ray powder diffraction, FT-IR Spectroscopy and Electron Transmission Microscopy. In order to analyse the effect of the nanoparticles’ surroundings on the excitation and relaxation processes of luminescent ions, Eu3+ ion was us…
Particle size-related limitations of persistent phosphors based on the doped Y3Al2Ga3O12 system
AbstractCo-doped Ce3+, Cr3+ and Pr3+ yttrium–aluminium–gallium garnet powders of various sizes were obtained by co-precipitation method. The microstructure and morphology were investigated by XRPD, TEM and gas porosimetry. The luminescence properties were studied by excitation and emission spectra, quantum yield and decay times. Thermoluminescence measurements were performed to evaluate the activation energy, traps redistribution and frequency factor. Limitation in the energy transfer between dopant ions in the small particles, traps depth and surface defects were considered and investigated as responsible for the quenching of persistent luminescence. The phosphors annealed at 1100 °C show …
Urea Glass Route as a Way to Optimize YAGG:Ce3+,Cr3+,Pr3+ Nanocrystals for Persistent Luminescence Applications
A new approach for the synthesis of Y3Al2Ga3O12 (YAGG) nanophosphors allowing the preparation of crystallites with sizes starting from 45 nm is presented. The controllability of the energy and trap density of the resulting material samples by annealing temperature was confirmed by thermoluminescence (TL) measurements. It has been shown that the annealing of samples at temperatures up to 1300 degrees C does not cause any substantial growth of crystallites, still remaining below 100 nm, but leads to changes in the activation energy of the persistent luminescence (PersL) process. On the other hand, annealing above 1400 degrees C results in grain growth on the submicron scale, which was confirm…