title: GdAlO3:Eu(3+):Bi(3+) nanophosphor: synthesis and enhancement of red emission for WLEDs.
abstract: GdAlO3, GdAlO3:Eu(3+) and GdAlO3:Eu(3+):Bi(3+) nanophosphors were synthesised by solution combustion technique. Pure orthorhombic phase was obtained from powder X-ray diffraction (PXRD) studies. Scanning electron microscopy (SEM) micrographs showed the porous, agglomerated and irregular shaped particles. The particle size obtained by transmission electron microscopy (TEM) measurement was in good agreement with the values obtained by Debye Scherrer's and W-H plots. The selected area electron diffraction (SAED) pattern show single crystalline nature of the sample. Photoluminescence (PL) measurements were carried out for GdAlO3:Eu(3+) and GdAlO3:Eu(3+):Bi(3+) phosphors excited at a wavelength of 274nm. The characteristic emission peaks of Eu(3+) ions were recorded at 590, 614, 655 and 695nm corresponding to (5)D0→(7)FJ (J=1, 2, 3, 4) transitions respectively. However, with addition of Bi(3+) ions in GdAlO3:Eu(3+), PL intensity drastically enhanced. Orange red color was tuned to deep red color with the addition of Bi(3+) ions in GdAlO3:Eu(3+) phosphor. Therefore, the phosphor was highly useful as red component in WLEDs. A single well resoled glow peak at 225°C was recorded in GdAlO3 and GdAlO3:Eu(3+). Further, with addition of Bi(3+) ions, an additional peak at 300°C was recorded. TL glow curves of different UV-exposed GdAlO3:Eu(3+):Bi(3+) show two TL peaks at 207 and 300°C respectively. The 207°C peak show simple glow peak structure and its intensity increases linearly up to 25min and after that it decrease.
authors.affiliation: Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India.
authors.forename: C J
authors.initials: CJ
authors.lastname: Shilpa
authors.affiliation: School of Process, Environmental and Materials Engineering, University of Leeds, Leeds LS2 9JT, UK.
authors.forename: Akila Kadgathur
authors.initials: AK
authors.lastname: Jayaram
authors.affiliation: Department of Physics, B.M.S. Institute of Technology, Bangalore 560 064, India.
authors.forename: N
authors.initials: N
authors.lastname: Dhananjaya
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, Bangalore 560 091, India. Electronic address: scphysics@gmail.com.
authors.forename: S C
authors.initials: SC
authors.lastname: Prashantha
authors.affiliation: Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103, India.
authors.forename: D V
authors.initials: DV
authors.lastname: Sunitha
authors.affiliation: Chhattisgarh Swami Vivekanand Technical University, Bhilai, CG 493 441, India.
authors.forename: S C
authors.initials: SC
authors.lastname: Sharma
authors.affiliation: Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India.
authors.forename: C
authors.initials: C
authors.lastname: Shivakumara
authors.affiliation: Department of Chemistry, M.S. Ramaiah Institute of Technology, Bangalore 560 054, India.
authors.forename: B M
authors.initials: BM
authors.lastname: Nagabhushana
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D001729:Bismuth / Q000737:chemistry*; D002412:Cations / Q000737:chemistry; D005063:Europium / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry*; D049449:Luminescence; D049408:Luminescent Agents / Q000737:chemistry*; D008958:Models, Molecular; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size
chemical_list: D002412:Cations; D049408:Luminescent Agents; D010087:Oxides; D005063:Europium; D005682:Gadolinium; D000535:Aluminum; D001729:Bismuth
keywords: Nanophosphor; Photoluminescence; Thermoluminescence; WLED