Найдено научных статей и публикаций: 3, для научной тематики: Phosphor
1.
Arunkumar Paulraj, Prabu Natarajan, Kottaisamy Munnisamy, Mujafar Kani Nagoor, Kamaraj Parimana Nattar, Burkanudeen Abdulrazak, and Jeyakumar Duraisamy
, 2011
No Abstract...
No Abstract
2.
Arunkumar Paulraj, Prabu Natarajan, Kottaisamy Munnisamy, Mujafar Kani Nagoor, Kamaraj Parimana Nattar, Burkanudeen Abdulrazak, and Jeyakumar Duraisamy
, 2010
Highly efficient yttrium oxide doped with trivalent europium (Y2O3:Eu) phosphor was prepared through precursors synthesized by hydrothermal method. Crystalline precursors, namely europium-doped yttrium carbonate (Y2(CO3)3.2H2O:Eu) and
europium-doped yttrium hydroxy carbonate(Y(OH)CO 3:Eu),were prepa...
Highly efficient yttrium oxide doped with trivalent europium (Y2O3:Eu) phosphor was prepared through precursors synthesized by hydrothermal method. Crystalline precursors, namely europium-doped yttrium carbonate (Y2(CO3)3.2H2O:Eu) and
europium-doped yttrium hydroxy carbonate(Y(OH)CO 3:Eu),were prepared by varying the concentration of yttrium to europium ions and urea in the reaction mixture. The precursor
materials on annealing at 700 C gave nanocrystalline Y2O3:Eu, which was further processed at high temperatures in the absence
and presence of sintering aid to yield phosphor materials with varying crystallite size and morphology. The precursors and phosphor material were characterized using FTIR, TGA,
powder XRD, SEM, TEM, and photoluminescence (PL) spectral studies. The emission efficiency was found to depend on the crystallite size, morphology, and particle size of the phosphor materials. It was observed that phosphor material with spherical
morphology and particle size of 0.5–1.0 micron with crystallite size of 100 nm has the highest PL efficiency.
3.
P. Arunkumar, C. Jayajothi, D. Jeyakumar and N. Lakshminarasimhan
- Journal of American Ceramic Society , 2012
Hexagonal BiPO4.xH2O and Bi0.95Eu0.05PO4.xH2O nanoparticles were synthesized by a polyol-
mediated method employing diethylene glycol. The powder X-ray diffraction revealed the phase
purity and isostructural nature of both undoped and Eu3+-doped BiPO4 . The monoclinic
Bi0.95Eu0.05PO4 was obtained b...
Hexagonal BiPO4.xH2O and Bi0.95Eu0.05PO4.xH2O nanoparticles were synthesized by a polyol-
mediated method employing diethylene glycol. The powder X-ray diffraction revealed the phase
purity and isostructural nature of both undoped and Eu3+-doped BiPO4 . The monoclinic
Bi0.95Eu0.05PO4 was obtained by heating the hexagonal Bi0.95Eu0.05PO4.xH2O at 600 C. The
microscopical characterization revealed the formation of nanocrystalline materials. Water molecules present in the bismuth precursor favoured the formation of hexagonal phase at low temperature. The role of DEG molecules in arresting the particle growth during the phase transformation of Bi0.95Eu0.05PO4 from hexagonal to monoclinic was observed. The synthesized materials were characterized using different spectroscopic techniques such as FT-IR, Raman,31P MAS-NMR,DRUV-Vis and PL. The difference in the crystal structures and symmetries is clearly reflected in the spectral results of hexagonal and monoclinic Bi0.95Eu0.05PO4. The structure-property relations were studied to derive its importance from both fundamental and technological aspects.