Search results for "Ce:YAG"
showing 8 items of 8 documents
Ce:YAG-PMMA nanocomposite for white LED
2012
Ce:YAG-PMMA composite was prepared by a melt compounding method. The characterization was performed using transmission electron microscopy, X-ray diffractometry, and photoluminescence spectroscopy. Results showed that Ce:YAG particles are well dispersed in the polymeric matrix. The luminescence properties of the nanocomposite do not show quenching or significant spectral shift indicating that the nanocomposite can be useful for advanced applications such as white LED construction.
Ce:YAG composites for white LED
2015
Composites and luminescent polymers have been recently found to be potential candidates for the development of white LED, lasers and luminescent concentrators for solar cells. Due to its luminescence properties YAG doped with lanthanides ions is a good candidate as light emitting filler. In a recent our work, the preparation of a polymeric nanocomposite containing Ce:YAG nanoparticles using in situ polymerization has been reported [1]. A good dispersion of Ce:YAG nanoparticles has been obtained maintaining them luminescence properties. In addition, an increase of thermal stability and stiffness of PMMA was observed [2]. Then, the preparation of Ce:YAG-PMMA composite has been performed by us…
Polymeric Ce:YAG nanocomposites: synthesis and characterization
2015
These last years, the development of hybrid polymer-inorganic nanocomposites has been attracted much attention. In particular, composites containing lanthanide-doped materials as filler are candidates for the development of light emitting diodes, lasers and solar cells. Polymers such as polymethylmethacrylate (PMMA), polycarbonate (PC) and polyurethane (PU) are adequate matrices because their good transmission over the visible spectral range, excellent mechanical properties of plasticity, lightness, easiness of fabrication and low cost of mass production. Yttrium aluminum garnet (YAG) doped with Ce(III) ions is one of the yellow phosphor used in the major commercial white LED combined with …
Synthesis of yttrium aluminum garnet nanoparticles in confined environment III: Cerium doping effect
2018
Abstract Cerium yttrium aluminum garnet (Ce:YAG, CexY3-xAl5O12) nanoparticles doped with different cerium amount were obtained by calcining the precursors synthesized via co-precipitation in w/o microemulsion for 1 h at 900 °C. The structural and morphological properties were investigated by using X-ray Diffraction (XRD), Infrared Spectroscopy (IR) and Transmission Electron Microscopy (TEM) coupled with Energy Dispersive X-ray Spectroscopy (EDS) in order to investigate the effect of doping level on formation and microstructure of obtained nanoparticles. It was found that the composition of the final products strongly depends on the concentration of cerium. The formation of single YAG phase …
Effect of the dopant selection (Er, Eu, Nd or Ce) and its quantity on the formation of yttrium aluminum garnet nanopowders
2008
Abstract Hydroxide precursors, synthesized using the co-precipitation method, were calcined for 1 h at the temperatures of 900, 1000 and 1100 °C, respectively, and heated directly to 1500 °C to produce various Y 3 Al 5 O 12 (YAG) nanopowders with different doping quantities of erbium, europium, neodymium and cerium. All samples were investigated using thermo-gravimetry (TG) and differential thermal analysis (DTA), field emission gun-scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). TG and DTA experiments were performed from room temperature up to 1500 °C; the weight loss curves combined with the presence of exo- and endo-thermal even…
Ce:YAG nanoparticles embedded in a PMMA matrix: preparation and characterization
2010
A Ce:YAG-poly(methyl methacrylate) composite was prepared using in situ polymerization by embedding the Ce:YAG nanopowder in a blend of methyl methacrylate (MMA) and 2-methacrylic acid (MAA) monomers and activating the photopolymerization using a radical initiator. The obtained nanocomposite was yellow and transparent. Its characterization was performed using transmission electron microscopy, small angle X-ray scattering, (13)C cross-polarization magic-angle spinning nuclear magnetic resonance, and photoluminescence spectroscopy. Results showed that Ce:YAG nanoparticles are well dispersed in the polymeric matrix whose structure is organized in a lamellar shape. The luminescence properties o…
Macro-micro relationship in nanostructured functional composites
2012
This paper examines the results of the characterization of two functional composites: Poly(methyl methacrylate) (PMMA)-Ce:YAG (yttrium aluminium garnet doped with cerium) and PMMA-cobalt hexacyanoferrate (CoHCF). The composites were prepared as possible emitters in the fields of lighting thermal sensors. The prepared composites were char- acterized using transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) spectroscopy, thermogravi- metric analysis (TGA), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) analyses to study the correlation between micro and macro characteristics. We found that the molecular interactions of the two different fill…
Sviluppo del metodo urea glass-route per la preparazione di nanoparticelle di Ce:YAG
2015
I materiali a base di yttrium aluminum garnet (YAG) drogato con ioni lantanidi hanno suscitato negli ultimi anni notevole interesse per le loro importanti applicazioni tecnologiche nel campo dei dispositivi optoelettronici quali laser, LED, display e scintillatori per i raggi X. In particolare, lo YAG drogato con ioni Ce(III) è utilizzato, in combinazione ai semiconduttori di nitruro di gallio (GaN) o indio e gallio (GaInN), per la realizzazione di LED a luce bianca1. Il miglioramento delle performance di questi dispositivi è vincolato all’ottimizzazione, in termini di proprietà, dei materiali che lo compongono. Una delle strategie consiste nel preparare nanoparticelle (np) di Ce:YAG con di…