Behavior of bismuth ions in the two glassy systems of 50 LiF-50 P2O5 and 50 LiF-50 B2O3 (mol %) assessed by optical, FTIR and photoluminescence spectra in addition to thermal expansion properties

Abstract

AbstractGlasses from two varieties of (LiF-B2O3) and (LiF-P2O5) systems with equal 50 mol % for each partner together with samples doped with 1 or 2% Bi2O3 were synthesized by melting–annealing mechanism. Multiple optical, FTIR and photoluminescence spectral measurements were carried out. Optical spectra of Bi2O3—doped glasses exhibit UV-near visible peaks owing to the specific absorption of Bi3+ ions. FTIR spectra elucidate the presence of characteristic vibrational bands from (LiF-B2O3) glass due to (BO3) and (BO3F) groups beside (LiF4) groups while the fluorophosphate glasses (LiF-P2O5) show vibrations due to PO4 and (PO3F) groups and also the possible sharing of (LiF4) groups. Photoluminescence spectral data reveal extended emission from about 375 to 700 nm and is more prominent in (LiF-B2O3) system than (LiF-P2O5) system. The thermal expansion data reveal similar behavior and the derived transition and softening temperatures are slightly lower in (LiF-P2O5) glasses than (LiF-B2O3) glasses.