title: A single phase, red emissive Mg2SiO4:Sm3+ nanophosphor prepared via rapid propellant combustion route.
abstract: Mg2SiO4:Sm3+ (1-11 mol%) nanoparticles were prepared by a rapid low temperature solution combustion route. The powder X-ray diffraction (PXRD) patterns exhibit orthorhombic structure with α-phase. The average crystallite size estimated using Scherer's method, W-H plot and strain-size plots were found to be in the range 25-50 nm and the same was confirmed by Transmission Electron Microscopy (TEM). Scanning electron microscopy (SEM) pictures show porous structure and crystallites were agglomerated. The effect of Sm3+ cations on luminescence of Mg2SiO4 was well studied. Interestingly the samples could be effectively excited with 315 nm and emitted light in the red region, which was suitable for the demands of high efficiency WLEDs. The emission spectra consists of four main peaks which can be assigned to the intra 4-f orbital transitions of Sm3+ ions 4G5/2→6H5/2 (576 nm), 4G5/2→6H7/2 (611 nm), 4G5/2→6H9/2 (656 nm) and 4G5/2→6H11/2 (713 nm). The optimal luminescence intensity was obtained for 5 mol% Sm3+ ions. The CIE (Commission International de I'Eclairage) chromaticity co-ordinates were calculated from emission spectra, the values (0.588, 0.386) were close to the NTSC (National Television Standard Committee) standard value of red emission. Coordinated color temperature (CCT) was found to be 1756 K. Therefore optimized Mg2SiO4:Sm3+ (5 mol%) phosphor was quite useful for solid state lighting.
authors: Department of Physics, New Horizon College of Engineering, Bangalore 560103, India; Research and Development Center, Bharathiar University, Coimbatore 641046, India.
authors: Ramachandra
authors: R
authors: Naik
authors: Research and Development Center, Bharathiar University, Coimbatore 641046, India; Research Center, Department of Science, East West Institute of Technology, Bangalore 560091, India. Electronic address: scphysics@gmail.com.
authors: S C
authors: SC
authors: Prashantha
authors: Prof. CNR Rao Center for Advanced Materials, Tumkur University, Tumkur 572103, India. Electronic address: bhushanvlc@gmail.com.
authors: H
authors: H
authors: Nagabhushana
authors: Chhattisgarh Swami Vivekananda Technical University, Bhilai (CG) 493441, India.
authors: S C
authors: SC
authors: Sharma
authors: Research Center, Department of Science, East West Institute of Technology, Bangalore 560091, India.
authors: H P
authors: HP
authors: Nagaswarupa
authors: Research Center, Department of Science, East West Institute of Technology, Bangalore 560091, India.
authors: K S
authors: KS
authors: Anantharaju
authors: Department of Chemistry, M.S. Ramaiah Institute of Technology, Bangalore 560054, India.
authors: B M
authors: BM
authors: Nagabhushana
authors: Department of Physics, Acharya Institute of Technology, Bangalore 560107, India.
authors: H B
authors: HB
authors: Premkumar
authors: Department of Physics, Dayanand Sagar Academy of Technology and Management, Bangalore 560082, India.
authors: K M
authors: KM
authors: Girish
mesh_terms: D049449:Luminescence; D049408:Luminescent Agents / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D012493:Samarium / Q000737:chemistry*; D017655:Silicon Compounds / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D049408:Luminescent Agents; D017655:Silicon Compounds; C503823:forsterite; D012493:Samarium
keywords: Combustion technique; Mg(2)SiO(4):Sm(3+); Nanophosphor; Photoluminescence; Solid state lighting; WLEDs