title: Role of flux on morphology and luminescence properties of Sm(3+) doped Y2SiO5 nanopowders for WLEDs.
abstract: The study involves preparation of samarium doped Y2SiO5 (YSO) nano powders by solution combustion method using urea as a fuel for the first time. Effect of different fluxes on the crystallization behavior, morphology and photoluminescence (PL) properties of YSO:Sm(3+) (1-9 mol%) were investigated. The final product was characterized by Powder X-ray diffraction (PXRD), Scanning Electron Microscopy (SEM) and UV-Vis spectroscopy. The average crystallite size estimated by Debye-Scherer's and Williamson-Hall plots were found to be in the range of 10-50 nm. Samples calcined at 1100°C show pure monoclinic X1 phase; whereas, samples calcined at 1200 and 1300°C show pure X2 phase of YSO. Photoluminescence (PL) studies of Sm(3+) (1-9 mol%) doped YSO for near ultra violet (NUV) excitation (407 nm) was studied in order to investigate the possibility of its use in white light emitting diode (WLED) applications. The emission spectra consists of intra 4f transitions of Sm(3+), such as (4)G5/2→(6)H5/2 (∼560 nm), (4)G5/2→(6)H7/2 (600-613 nm), (4)G5/2→(6)H9/2 (∼650 nm), (4)G5/2→(6)H11/2 (715 nm) and (4)G5/2→(6)H13/2 (763 nm) respectively. The emission intensity of the phosphor was found to be enhancing after addition of fluxes. Further, the emission at 600-613 nm show strong orange-red emission and can be applied to the orange-red emission of phosphor for near ultra violet excitation.
authors.affiliation: Department of Physics, University College of Science, Tumkur University, Tumkur 572 103, India.
authors.forename: G
authors.initials: G
authors.lastname: Ramakrishna
authors.affiliation: Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India. Electronic address: bhushanvlc@gmail.com.
authors.forename: H
authors.initials: H
authors.lastname: Nagabhushana
authors.affiliation: Research Center, Department of Physics, East West Institute of Technology, Bengaluru 560 091, India. Electronic address: scphysics@gmail.com.
authors.forename: S C
authors.initials: SC
authors.lastname: Prashantha
authors.affiliation: Chhattisgarh Swami Vivekanand Technical University, Bhilai, CG 493 441, India.
authors.forename: S C
authors.initials: SC
authors.lastname: Sharma
authors.affiliation: Department of Chemistry, M.S. Ramaiah Institute of Technology, Bengaluru 560 056, India.
authors.forename: B M
authors.initials: BM
authors.lastname: Nagabhushana
mesh_terms: D004581:Electronics; D004583:Electrons; D049449:Luminescence; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry*; D011208:Powders; D012493:Samarium / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D017655:Silicon Compounds / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D014961:X-Ray Diffraction; D015019:Yttrium / Q000737:chemistry*
chemical_list: D010087:Oxides; D011208:Powders; D017640:Silicates; D017655:Silicon Compounds; D012493:Samarium; D015019:Yttrium
keywords: Combustion synthesis; Phosphor; Photoluminescence; Rare earth ions; Y(2)SiO(5):Sm(3+)