title: Synthesis, structural and luminescence studies of magnesium oxide nanopowder.
abstract: Nanoparticles of magnesium oxide (MgO) have been prepared by low temperature solution combustion and hydrothermal method respectively. Powder X-ray diffraction (PXRD) patterns of MgO samples prepared by both the methods show cubic phase. The Scanning Electron Microscopy (SEM) studies reveal, the combustion derived product show highly porous, foamy and fluffy in nature than hydrothermally derived sample. The optical absorption studies of MgO show surface defects in the range 250-300 nm. The absorption peak at ∼290 nm might be due to F-centre. Photoluminescence (PL) studies were carried upon exciting at 290 nm. The sample prepared via combustion method show broad emission peak centred at ∼395 nm in the bluish-violet (3.14 eV) region. However, in hydrothermal prepared sample show the emission peaks at 395 and 475 nm. These emission peaks were due to surface defects present in the sample since nanoparticles exhibits large surface to volume ratio and quantum confinement effect.
authors.affiliation: Centre for Nano Research (CNR), Tumkur University, Tumkur 572 103, India; Department of Physics, RV College of Engineering, Bangalore 560 091, India.
authors.forename: P B
authors.initials: PB
authors.lastname: Devaraja
authors.forename: D N
authors.initials: DN
authors.lastname: Avadhani
authors.forename: S C
authors.initials: SC
authors.lastname: Prashantha
authors.forename: H
authors.initials: H
authors.lastname: Nagabhushana
authors.forename: S C
authors.initials: SC
authors.lastname: Sharma
authors.forename: B M
authors.initials: BM
authors.lastname: Nagabhushana
authors.forename: H P
authors.initials: HP
authors.lastname: Nagaswarupa
mesh_terms: D003460:Crystallization; D049449:Luminescence; D008277:Magnesium Oxide / Q000138:chemical synthesis / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D016062:Porosity; D011208:Powders; D014961:X-Ray Diffraction
chemical_list: D011208:Powders; D008277:Magnesium Oxide
keywords: Combustion synthesis; Hydrothermal method; Optical absorption; Phosphor; Photoluminescence