Third Day Poster Session, 17 June 2010 - NanoTR-VI

Poster Session, Thursday, June 17
Theme F686 - N1123
Optical and Structural Characterization of Y 2 O 3 :Nd 3+ Phosphors via Thermal Decomposition Method
G. Bilir* and G. Özen
Department of Physics, stanbul Technical University, Maslak-stanbul 34469, Turkey
Abstract: The Y 2 O 3 :Nd 3+ nanophosphors were synthesized by using thermal decomposition method. The powders were annealed at different
temperatures to investigate annealing temperature dependence of the crystallite size. Average particle size of the products were calculated by
using Scherrer Formula from the X-ray diffractograms Luminescence measurement were performed for all samples at room temperature. Also
SEM/EDS measurements were confirmed the calculated particle sizes from XRD diffractograms.
Materials with nanostructure attracted considerable attention
because of potential applications in optoelectronics and
photonics[1-4]. Phosphor materials find wide applications
ranging from fluorescent lamp to luminescence immunoassay.
These materials essentially convert one type of energy into
visible radiation and hence, phosphor materials are called
optical transducer[5].
In this work nanosized Y 2 O 3 samples doped with x=0.2, 0.5,
1, 2, 5, 10 mol% Nd 3+ ions (Y 2-x Nd x O 3 ) were prepared by
thermal decomposition of yttrium-neodymium alginate.
Obtained products were annealed at 600, 800 and 1000 to
investigate particle size dependence on annealing temperature.
X-ray diffraction investigations were carried out with
Philips TM model(Cu-K) diffractometer at 40 kV in the 2 range
from 20 o to 60 o . Also SEM images of the samples were taken by
using JEOL 6335F model scanning electron microscope(SEM).
Both of XRD and SEM measurements show that the particle
sizes of Y 2 O 3 :Nd 3+ samples were ranging from 20nm to 40 nm
which are consistent with the values reported in literature[6].
Representative X-ray diffractograms and SEM images are given
in Figs.1-2.
Princeton Instruments SP2500i model monochromator and
Acton series ID441-C Model InGaAs detector for the
detection.
PL measurements were performed at room temperature and
strong PL intensities were obtained for all Nd 3+ doped
samples. The PL spectra of all samples are consist of three
spectral regions which were correspond to the 4 F 3/2 4 I 9/2 ,
4 F 3/2 4 I 11/2 and 4 F 3/2 4 I 13/2 transitions of theNd 3+ . In Fig.2
representative of PL of 0.5% Nd 3+ doped sample are given.
Figure 3: PL of 0.5% Nd 3+ doped Y 2O 3
Also in Fig. 4, the dependence of FWHM(full width at half
maxima) of the transitions on annealing temperature is given.
Figure 1: XRD patterns of the non-annealed Y 2O 3:Nd 3+ nanopowders
Figure 2: SEM images of the %0,5Nd doped Y 2O 3 annealed at 1000C (left) and
non-annealed (right)
From SEM images also seen that the organic
component(alginate) from synthesis method which used to
form yttrium alginate gels is exist for non-annealed samples
and it was observed for all samples. The emission spectra were
collected by using Apollo Instruments diode laser (Model No:
S30-808-6) with 805.2 nm wavelength as an excitation source,
Figure 4:Annealing temperature dependence of the FWHM
SEM measurements were supported by Science Institute of
Marmara University with the project number FEN-CDRP-
090409-0079
*bilirg@itu.edu.tr
References
[1]Promod and et al, Journal of Luminescence, 82 (1999) 187-193
[2] Hai Huang and et al, Nanotechnology, 13 (2002) 318-323
[3] Gino Tessari, Marco Bettinelli and et al., Applied Surface Science,
144-145 (1999) 686-689
[4] Michael Nazarov and et al, Optical Materials, 27 (2005) 1587-1592
[5] T. Kim Anh and et al, Journal of Luminescence, 102-103 (2003)
391-394
[6] D. Tatar, H. Kaygusuz, F. Tezcan, FB. Erim, ML. Oveçolu, G.
Ozen “Y2O3 Nanophosphors Synthesized by Combustion and Thermal
Decomposition Techniques” 11th Annual Conference on NanoScience
and NanoTechnology, NSTI-NanoTech, Boston-USA (MO81-919)
(June 1-5/2008)
6th Nanoscience and Nanotechnology Conference, zmir, 2010 617