Structural and Mechanical Properties of Lithium Bismuth Borate Glasses Containing Molybdenum (LBBM) Together with their Glass–Ceramics

• Published in: Journal of inorganic and organometallic polymers and materials 2021-03, Vol.31 (3), p.1057-1065
• Main Authors: El-Rehim, A. F. Abd, Shaaban, Kh. S., Zahran, H. Y., Yahia, I. S., Ali, Atif Mossad, Halaka, M. M. Abou, Makhlouf, Sayed A., Wahab, E. A. Abdel, Shaaban, E. R.
• Format: Article
• Language: English
• Subjects: Bismuth; Chemistry; Chemistry and Materials Science; Energy of dissociation; Free energy; Functional groups; Glass ceramics; Heat of formation; Infrared spectroscopy; Inorganic Chemistry; Lithium borates; Mechanical properties; Modulus of elasticity; Molar volume; Molybdenum oxides; Molybdenum trioxide; Organic Chemistry; Polymer Sciences; Spectrum analysis; Thermal stability
• ISSN: 1574-1443; 1574-1451
• DOI: 10.1007/s10904-020-01708-1

This study reports that MoO 3 doped glasses (LBB) are produced by a melting traditional process and using the XRD diffractometer technique to check their states. FTIR spectral analysis has examined the functional groups of the glass matrix. FT-IR spectrums reveal that the BO 3 , BO 4 . BiO 6 and MoO 6 octahedral have been built up and structural unit BO 3  was transformed into BO 4 . The mechanical characteristics were linked to the FT-IR spectrum results. Ultrasonic velocities, elastic modulus, density, and thermal stability increased, while molar volume decreased. The increase in these parameters is linked with [BO 4 ] the formation of structural units, an increase the strength of Mo – O, and force constant is higher than Li – O, so glass rigidity increases. Therefore, the increase of MoO 3 usually has a significant influence on the bridging oxygen (BO) formation in BBL glasses. The increase in thermal stability connected to an increase in average force constantly, and the replacement of Li–iO with Mo–O linkages. The bond dissociation energy of Li–Li (137.3 ± 6.3 kJ/mol) is much weaker than the dissociation energy of Mo–Mo (449 ± 1 kJ/mol). Lithium borate Li 2 B 4 O 7 (diomignite) has been identified in all formed glass–ceramics. With the increasing MoO 3 , the intensity of diomignite diffraction peaks (Li 2 B 4 O 7 ) was reduced and transformed into a less stable lithium borate (Li 2 B 2 O 5 ) phase.