Optical properties of Eu 2+-doped strontium borate glasses containing F − and Li + ions

Abstract

In this experiment, strontium borate glasses were prepared using the conventional quenching method in air atmosphere. Optical absorption, photoluminescence excitation and emission spectra, X-ray excited luminescence (XEL), and luminescence decay curve of the as-prepared glasses were investigated at room temperature. The as-prepared glasses had two kinds of Eu ions, i.e., Eu 2+ and Eu 3+. Compared with the reported results of strontium borate glasses, Eu 2+ luminescence was enhanced in the studied strontium borate glasses coprepared with F − and Li + ions. The coexisting of Li + or F − in the borate glasses could create more negative defect V Sr? and stabilize Eu 2+ ions, which might act as donor of electrons; For the F − doping, the new center of B(O, F) 4 (or BO 3F) and BO 2F 2 units could be considered to be the distorted (BO 4), which were needed as a rigid framework to stabilize the divalent rare earth ions.