DFT and synchrotron radiation study of Eu 2+ doped BaAl 2 O 4

The structural distortions resulting from the size mismatch between the Eu2+ luminescent centre and the host Ba2+ cation as well as the electronic structure of BaAl2O4:Eu2+(,Dy3+) were studied using density functional theory (DFT) calculations and synchrotron radiation (SR) luminescence spectroscopy. The modified interionic distances as well as differences in the total energies indicate that Eu2+ prefers the smaller of the two possible Ba sites in the BaAl2O4 host. The calculated Eu2+ 4f7 and 4f65d1 ground level energies confirm that the excited electrons can reach easily the conduction band for subsequent trapping. In addition to the green luminescence, a weak blue emission band was observed in BaAl2O4:Eu2+,Dy3+ probably due to the creation of a new Ba2+ site due to the effect of water exposure on the host.

[1]  M. Lastusaari,et al.  Persistent luminescence behavior of materials doped with Eu 2+ and Tb 3+ , 2012 .

[2]  M. Lastusaari,et al.  Defect aggregates in the Sr2MgSi2O7 persistent luminescence material , 2011 .

[3]  M. Lastusaari,et al.  Thermoluminescence and synchrotron radiation studies on the persistent luminescence of BaAl2O4:Eu2+,Dy3+ , 2010 .

[4]  M. Lastusaari,et al.  Persistent luminescence of Eu2+ and Dy3+ doped barium aluminate (BaAl2O4:Eu2+,Dy3+) materials. , 2009 .

[5]  H. Jiao,et al.  Luminescent properties of stabled hexagonal phase Sr1−xBaxAl2O4:Eu2+ (x=0.37–0.70) , 2009 .

[6]  M. Lastusaari,et al.  Synchrotron radiation investigations of the Sr2MgSi2O7:Eu2+,R3+ persistent luminescence materials , 2009 .

[7]  Yun Liu,et al.  Distortion modes and related ferroic properties of the stuffed tridymite-type compounds SrAl 2 O 4 and BaAl 2 O 4 , 2009 .

[8]  M. Peng,et al.  Reduction from Eu3+ to Eu2+ in BaAl2O4:Eu phosphor prepared in an oxidizing atmosphere and luminescent properties of BaAl2O4:Eu , 2007 .

[9]  Didier Gourier,et al.  Nanoprobes with near-infrared persistent luminescence for in vivo imaging , 2007, Proceedings of the National Academy of Sciences.

[10]  B. Kukliński,et al.  High-pressure luminescence spectroscopy of EuAl2O4 phosphor , 2007 .

[11]  W. Pickett,et al.  Exact exchange for correlated electrons , 2006 .

[12]  A. Winnacker,et al.  The influence of lattice defects on fluorescence and phosphorescence in the europium aluminate EuAl2O4 , 2005 .

[13]  Z. Fu,et al.  Band structure calculations on the monoclinic bulk and nano-SrAl2O4 crystals , 2005 .

[14]  P. Dorenbos.  Systematic behaviour in trivalent lanthanide charge transfer energies , 2003 .

[15]  A. Halperin.  Activated thermoluminescence (TL) dosimeters and related radiation detectors , 2000 .

[16]  Eiichiro Nakazawa,et al.  Traps in SrAl2O4:Eu2+ phosphor with rare-earth ion doping , 1997 .

[17]  Hajime Yamamoto,et al.  Mechanism of long phosphorescence of SrAl2O4:Eu2+, Dy3+ and CaAl2O4:Eu2+, Nd3+ , 1997 .

[18]  A. Lichtenstein,et al.  First-principles calculations of electronic structure and spectra of strongly correlated systems: the LDA+U method , 1997 .

[19]  P. Dederichs,et al.  Corrected atomic limit in the local-density approximation and the electronic structure of d impurities in Rb. , 1994, Physical review. B, Condensed matter.

[20]  W. Hörkner,et al.  Zur Kristallstruktur von BaAl2O4 , 1979 .

[21]  R. D. Shannon.  Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides , 1976 .