In an ongoing effort towards a more sustainable rare-earth element market, there is high potential for efficient recycling of elements from end-of-life compact fluorescent lamps by physical separation the individual phosphors. this study, we investigate five lamp particles high-gradient magnetic in rotary permanent magnet separator. We thoroughly characterize phosphors ICP-MS, laser diffraction...

Transition metal ions doped NaCaAlPO4F3 phosphors have been synthesized using a solid state reaction method. The prepared samples are characterized by powder XRD, SEM, optical absorption, EPR, PL and FT-IR techniques. The XRD studies confirm the crystal structure of prepared phosphor samples as monoclinic system. SEM images show nanoclusters. Optical absorption and EPR spectra of TM ions doped ...

Rare-earth doped oxynitrides have attracted much attention as phosphors for white LEDs. A new family of Ce or Eu-doped oxynitride phosphors with the apatite structure has been studied: La8+xSr2-x(Si/Ge)6NyO26+x/2-3/2y. The ammonolysis of an apatite oxide precursor has been used as a general method of synthesis, allowing decreasing the nitriding temperature respective to the classical solid stat...

OBJECTIVE to study various phosphors used in detectors of medical imaging systems by the gain transfer function (GTF), defined in terms of X-ray luminescence efficiency, light spectrum and modulation transfer function. MATERIALS AND METHODS four phosphor materials, La(2)O(2)S:Tb, Y(2)O(2)S:Tb, Y(2)O(2)S:Eu and Y(2)O(3):Eu were used in the form of fluorescent layers prepared in the laboratory....

Persistent luminescent materials are able to emit light for hours after being excited. The majority of persistent phosphors emit in the blue or green region of the visible spectrum. Orange- or red-emitting phosphors, strongly desired for emergency signage and medical imaging, are scarce. We prepared the nitrido-silicates Ca₂Si₅N₈:Eu (orange), Sr₂Si₅N₈:Eu (reddish), Ba₂Si₅N₈:Eu (yellowish orange...

A method is developed to fabricate monodispersed biocompatible Yb/Er or Yb/Tm doped β-NaGdF4 upconversion phosphors using polyelectrolytes to prevent irreversible particle aggregation during conversion of the precursor, Gd2 O(CO3 )2.H2 O:Yb/Er or Yb/Tm, to β-NaGdF4 :Yb/Er or Yb/Tm. The polyelectrolyte on the outer surface of nanophosphors also provided an amine tag for PEGylation. This method i...

Abstract This review paper discusses the basics of optically stimulated luminescence (OSL) phenomenon, phosphors for OSL, functional design OSL phosphors, and application areas such as radiation dose monitoring individual environmental, computed radiography medical dental diagnosis, dating, security, archaeological autoradiography drug discovery. Finally, future prospects phenomenon passive-typ...

The nonradiative deactivation of the excited state of europium(III)-based phosphors via OH-vibrations in the presence of water allows the detection of moisture in nitrogen at concentration levels down to at least 25 ppm (0.09% RH).

The modification effect of the doping of Yb ions, as an auxiliary activator, onto the luminescent properties of SrAl2O4:Eu , Dy phosphor was studied for the first time. The phosphorescent nanoparticles were prepared by the combustion method. The experimental results indicate that the appropriate doping of Yb ions largely improves phosphorescence of the phosphors with more intense luminescence, ...

In 1996, Matsuzawa et al. reported on the enormously long-lasting afterglow of SrAl2O4: Eu 2+ co-doped with Dy ions, which was more than 10-times brighter than the previously widely used ZnS: Cu. Since then, research for stable and efficient phosphors has constantly gained attractiveness. However, even today almost 15 years after the invention of SrAl2O4: Eu 2+ the number of luminescent materia...