Structural characterization of sulphate borophosphate glasses containing calcium oxide

Abstract

Increasing demands for better perfoming glasses have lead to current investigating of the sturctural properties of glasses for optimum performances. Calcium sulphate borophosphate glasses of different compositions were prepared using melt quenching technique. The glass forming ability and stability were checked using Differential thermal analyzer (DTA). Density and molar volume had been evaluated and analyzed. From the results of XRD, the absent of discrete and continuous sharp peaks confirmed the amorphous nature of the glass compositions while the results from both IR and Raman revealed the existence of SO4, BO4, BO3, P-O-P and PO43-. Addition of CaSO4 to borophosphate influenced the conversion of the dominant BO3 groups to BO4 groups. The structure of the samples was mainly based on metaphosphate, diphosphate and BO4 units, which became depolymerized with addition of CaSO4 content. The glass forming ability and thermal stability were found to increase with an increase in the concentration of modifier content. Glass density and molar volume is found to be between 2.146 to 2.314 gcm-3 and 45.794 to 48.880 m3mol-1 respectively. It is observed that the density of glass increased while the molar volume also increased with respect to increase in concentration of CaSO4 in the glass compositions. We analysed our data using different mechanisms and compared the results with previous works. Our findings show that this glass could be beneficial and considered as a good candidate for optical devices applications.

Structural and spectroscopic investigations of neodymium‐doped strontium borophosphate glass

“…(SBP:Ce), [32] and showed that T g , T c , and T m increased with increasing (ZSBP) [19] and glass prepared in the present study suggested that the ΔT and K H can be increased by addition of lithium. However, comparatively higher values of T g , T c , and K H have been reported for [33] [34] also showed similar trends but ΔT was comparatively low. For optical fibres, glass with higher ΔT (>100 C) are preferred to fabricate crystal-free fibre with minimal scattering loss.…”

“…[36] The band at 570 cm À1 was due to the bending mode of the PO 4 3À unit. [34] The bending and stretching modes of BO 4 units were observed at c. 720 and 1020 cm -1, respectively. [37] The nonexistence of the boroxol rings was reflected through the absence of a peak c. 806 cm À1 .…”

Evaluation of the dynamic behavior, elastic properties, and in vitro bioactivity of some borophosphosilicate glasses for orthopedic applications

“…The reason for this result is that the successive increase in the content of B 2 O 3 , at the expense of P 2 O 5 , increases the number of NBOs as a result of the conversion of some Q 2 units to Q 1 ones, which was con rmed by the obtained FTIR spectra, that leads to a slight decrease in the density. This explanation is supported by the results discussed by Yamusa et al [57], who reported that the increase in the number of NBOs in the glass structure is responsible for decreasing the density of the glass samples. It should be noted that because B 2 O 3 is a network former, the density values are not always a good indicator of the packing density within the glass structure [58].…”