Synthesis and characterization of Ce3+ doped silica (SiO2) nanoparticles

Abstract A series of silica doped with different mol percentages of Ce3+ concentration was synthesized using a sol–gel method to determine the dependence of photoluminescence wavelengths and intensity on the concentrations of the dopants. Sol–gel glasses are porous networks that have been densified through chemical processing and heat treatment. Rare-earths (REs) are insoluble in silica; due to this insolubility RE ions in silicate glasses enter as network modifiers and compete for non-bridging oxygen in order to complete their coordination. The morphological, structural, thermal and optical properties of the phosphors were characterized by X-ray diffraction, scanning electron microscopy, UV–vis absorption, photoluminescence, thermogravimetric analyses and differential scanning calorimeter. Silica (SiO2) gel containing Ce3+ ions was sputter coated with Au (gold) in order to monitor surface morphology of the samples. The highest emission intensity was found for the sample with a composition of 0.5 mol% Ce3+. Cerium doped silica glasses had broad blue emission corresponding to the 2D3/2–2FJ transition at 448 nm but exhibited apparent concentration quenching above concentrations of 0.5 mol% Ce3+.

[1]  G. Stucky,et al.  Visible and near-IR luminescence via energy transfer in rare earth doped mesoporous titania thin films with nanocrystalline walls , 2003 .

[2]  D. Ganguli,et al.  Spectroscopic properties of cerium in glasses and their comparison with crystals , 1998 .

[3]  Yanchun Han,et al.  Sol–gel fabrication, patterning and photoluminescent properties of LaPO4:Ce3+, Tb3+ nanocrystalline thin films , 2003 .

[4]  D. Ganguli,et al.  Paramagnetic centers in unirradiated boron-doped silica gel , 1992 .

[5]  Renata Reisfeld,et al.  Spectroscopic properties of cerium in sol–gel glasses , 1999 .

[6]  M. El-Sayed,et al.  Thermal Reshaping of Gold Nanorods in Micelles , 1998 .

[7]  G. I. Brown.  Introduction to inorganic chemistry , 1957 .

[8]  A. K. Tyagi,et al.  SnO2: Eu3+ nanoparticles dispersed in TiO2 matrix: Improved energy transfer between semiconductor host and Eu3+ ions for the low temperature synthesized samples , 2007 .

[9]  J. Misiewicz,et al.  Nature and optical behaviour of heavily europium-doped silica glasses obtained by the sol-gel method , 2002 .

[10]  A. Steckl,et al.  Spectral and time-resolved photoluminescence studies of Eu-doped GaN , 2003 .

[11]  G. E. Malashkevich,et al.  New optical centers of triply charged cerium ions in silica gel-glasses saturated with hydrogen , 1999 .

[12]  Bruce Dunn,et al.  Photonic Materials by the Sol-Gel Process , 1991 .

[13]  A. Kulkarni,et al.  Melt mixed composites of poly(ethylene-co-methacrylic acid) ionomers and multiwall carbon nanotubes: influence of specific interactions. , 2008, Journal of Nanoscience and Nanotechnology.

[14]  Guang-yan Hong,et al.  Synthesis and luminescence properties of nanocrystalline Gd2O3:Eu3+ by combustion process , 2007 .

[15]  Pieter G. Kik,et al.  Energy backtransfer and infrared photoresponse in erbium-doped silicon p–n diodes , 2000 .

[16]  Chunhua Yan,et al.  Hydrothermal homogeneous urea precipitation of hexagonal YBO3:Eu3+ nanocrystals with improved luminescent properties , 2003 .

[17]  P. Dorenbos,et al.  Luminescence of Ce3+ ions in strontium haloborates , 2001 .

[18]  W. Cai,et al.  Reversible emission enhancement for Ce3+-doped silica nanoparticles dispersed within pores of mesoporous silica , 2000 .

[19]  L. Klein.  Sol-Gel Processing of Silicates , 1985 .

[20]  K. Hoffman,et al.  Effects of rehydration on Tb3+ spectroscopy in sol–gel glasses , 2007 .

[21]  Yue-hua Xu,et al.  The preparation, characterization, and photocatalytic activities of Ce-TiO2/SiO2 , 2008 .

[22]  R. Boscaino,et al.  The landscape of the excitation profiles of the αE and β emission bands in silica , 1999 .

[23]  Renata Reisfeld,et al.  Prospects of sol-gel technology towards luminescent materials , 2001 .

[24]  F. Dejene,et al.  The effect of Mg2+ ions on the photoluminescence of Ce3+-doped silica , 2009 .

[25]  Wai Kin Chan,et al.  Effect of γ-ray irradiation on structures and luminescent properties of nanocrystalline MSO4:xEu3+ (M = Ca, Sr, Ba; x = 0.001-0.005) , 2000 .