SAIP2015

Influence of alkaline earth metal cations; Ca²⁺, Sr²⁺ and Ba²⁺ on the structural and optical properties of MAl₂O₄: Eu²⁺, Nd³⁺ phosphors.

30 Jun 2015, 16:10

1h 50m

Board: A.073

Poster Presentation Track A - Division for Physics of Condensed Matter and Materials Poster1

Speaker

Mr ALI HALAKE WAKO (University of the Freestate)

Apply to be<br> considered for a student <br> &nbsp; award (Yes / No)?

Yes

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?

Yes

Main supervisor (name and email)<br>and his / her institution

Dejene B.F
dejenebf@qwa.ufs.ac.za
University of the Free State

Abstract content <br> &nbsp; (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>

Eu²⁺ doped and Nd³⁺ co-doped MAl₂O₄:Eu²⁺, Nd³⁺ (M = Ca, Sr, and Ba) phosphors were prepared by a solution-combustion method. XRD analysis depicts a monoclinic phase for CaAl₂O₄:Eu²⁺, Nd³⁺ and SrAl₂O₄:Eu²⁺, Nd³⁺ and a hexagonal structure for BaAl₂O₄:Eu²⁺, Nd³⁺ phosphor. SEM results showed generally agglomerated particles with non-uniform shapes and sizes with irregular network structures having lots of voids and pores. PL revealed broadband spectra corresponding to the 4f⁷-4f⁶5d¹ absorption and emission of Eu²⁺.Sharp emission lines were observed at 612 and 652 nm for CaAl₂O₄:Eu²⁺, Nd³⁺, at 615 nm for SrAl₂O₄:Eu²⁺, Nd³⁺ and at 610 nm for BaAl₂O₄:Eu²⁺, Nd³⁺ arising from the f-f transitions of the Eu³⁺ ions. The differences in emissions arise from the crystal field splitting of the 5d electron shell due to the changes in the crystalline environment of the Eu²⁺ ions caused by the substitution of the divalent alkaline earth metal cations in the host lattice.UV-VIS spectra showed absorption edges at 330,342 and 340 nm in agreement with the observed PL excitation peaks.

Please indicate whether<br>this abstract may be<br>published online<br>(Yes / No)

Yes

Level for award<br>&nbsp;(Hons, MSc, <br> &nbsp; PhD, N/A)?

PhD