Synthesis, EPR and luminescent properties of YAlO3:Fe3+ (0.1-0.9mol%) nanopowders

Spectrochim Acta A Mol Biomol Spectrosc. 2014 May 21:126:220-6. doi: 10.1016/j.saa.2014.01.141. Epub 2014 Feb 12.

Abstract

A simple and inexpensive combustion method was used to prepare Fe(3+) doped YAlO3 perovskite within few minutes at low temperature (400±10°C). This might be useful in lowering the cost of the material. The final products were well characterized by various spectroscopic techniques such as PXRD, SEM, TEM, FTIR and UV-Visible. The average crystallite size was estimated from the broadening of the PXRD peaks and found to be in the range 45-90nm, the results were in good agreement with the W-H plots and TEM. The crystallites show dumbbell shape, agglomerated particles with different size. The TL glow curves of 1-5kGy γ-irradiated YAlO3:Fe(3+) (0.1mol%) nanopowder warmed at a heating rate of 3°Cs(-1) records a single glow peak at ∼260°C. The kinetic parameters namely activation energy (E), order of kinetics (b) and frequency factor (s) were determined at different gamma doses using the Chens glow peak shape method and the results were discussed in detail. The photoluminescence spectra for Fe(3+) (0.1-0.9mol%) doped YAlO3 records the lower energy band at 720nm ((4)T1 (4G)→(6)A1 (6S)) and the intermediate band located at 620nm ((4)T2 ((4)G)→(6)A1 (6S)) with the excitation of 378nm. The higher energy band located at 514nm was associated to (4)E+(4)A1 ((4)G)→(6)A1 (6S) transition. The resonance signals at g values 7.6, 4.97, 4.10, 2.94, 2.33 and 1.98 were observed in EPR spectra of Fe(3+) (0.1-0.9mol%) doped YAlO3 recorded at room temperature. The g values indicate that the iron ions were in trivalent state and distorted octahedral site symmetry was observed.

Keywords: Combustion synthesis; Optical absorption; Phosphor; Photoluminescence.

MeSH terms

  • Aluminum Compounds / chemical synthesis
  • Aluminum Compounds / chemistry*
  • Calcium Compounds / chemical synthesis
  • Calcium Compounds / chemistry
  • Cations / chemical synthesis
  • Cations / chemistry
  • Electron Spin Resonance Spectroscopy
  • Iron / chemistry*
  • Luminescence
  • Luminescent Agents / chemical synthesis
  • Luminescent Agents / chemistry*
  • Luminescent Measurements
  • Nanoparticles / chemistry
  • Nanoparticles / ultrastructure
  • Oxides / chemical synthesis
  • Oxides / chemistry
  • Powders
  • Spectrophotometry, Ultraviolet
  • Spectroscopy, Fourier Transform Infrared
  • Titanium / chemistry
  • X-Ray Diffraction
  • Yttrium / chemistry*

Substances

  • Aluminum Compounds
  • Calcium Compounds
  • Cations
  • Luminescent Agents
  • Oxides
  • Powders
  • perovskite
  • Yttrium
  • Titanium
  • Iron