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
F.H. ElBatal, M. A. Marzouk, H.A. ElBatal, Y.M. Hamdy
Abstract
Abstract Glasses from two varieties of (LiF-B 2 O 3 ) and (LiF-P 2 O 5 ) systems with equal 50 mol % for each partner together with samples doped with 1 or 2% Bi 2 O 3 were synthesized by melting–annealing mechanism. Multiple optical, FTIR and photoluminescence spectral measurements were carried out. Optical spectra of Bi 2 O 3 —doped glasses exhibit UV-near visible peaks owing to the specific absorption of Bi 3+ ions. FTIR spectra elucidate the presence of characteristic vibrational bands from (LiF-B 2 O 3 ) glass due to (BO 3 ) and (BO 3 F) groups beside (LiF 4 ) groups while the fluorophosphate glasses (LiF-P 2 O 5 ) show vibrations due to PO 4 and (PO 3 F) groups and also the possible sharing of (LiF 4 ) groups. Photoluminescence spectral data reveal extended emission from about 375 to 700 nm and is more prominent in (LiF-B 2 O 3 ) system than (LiF-P 2 O 5 ) system. The thermal expansion data reveal similar behavior and the derived transition and softening temperatures are slightly lower in (LiF-P 2 O 5 ) glasses than (LiF-B 2 O 3 ) glasses.