Photoluminescent behavior of SrB4O7:RE2+ (RE = Sm and Eu) prepared by Pechini, combustion and ceramic methods

This work reports the preparation of system containing RE2+ ions (RE = Sm and Eu)-doped in SrB4O7 matrix by ceramic, Pechini and combustion methods. These compounds were prepared by reduction of RE(3+)to RE2+ in air, which exhibit some different features according to the preparation method. Photolurninescent properties of these systems were investigated based on the emission and excitation spectral data. The emission spectra of SrB4O7:Eu2+ system prepared by combustion and Pechini methods are characterized by a broad band assigned to interconfigurational 4f(6)5d -> 4f(7) transition, while SrB4O7Sm2+ compound exhibit narrow emission bands arising from intraconfigurational-4f(6) also shows (4)G(5/2) -> H-6(r) transitions (J' = (5)(2), (7)(2), (9)(2) and (11)(2)) arising from Sm3+ ion, transitions. 9 _11 212 -ed by combustion method presents emission bands from RE tons as intense as that arising from Re2+. SrB4O7:RE system prepat 3 + suggesting that the preparation route is not efficient for the reduction RE3+ -> RE2+ process. Emission quantum efficiency and radiative emission rates of Sm2+ ion are determined and discussed. (c) 2006 Elsevier Inc. All rights reserved.