Microstructure of barium-vanadate glasses

The structure of barium-vanadate glasses was measured by SEM and XRD techniques. Samples of the composition of xBaO-(100-x)V2O5 where x= 30, 40 and 45 (in %mol) were prepared by the conventional melt quenching technique. Appropriate amounts of reagents: BaO (≥99.9%, P.P.H STANLAB Sp.J.) and V2O5 (≥99.9%, POCH) were thoroughly mixed in an agate mortar. The melting was performed in porcelain crucibles at 1273 K for 10–30 min, depending on glass composition. The melts were poured on preheated (to 393 K) brass plate and pressed by another plate to obtain flat circular pellets of 1-2 mm thickness and 10-20 mm in diameter.The structure has been studied by the X-ray diffraction method with the use of a Philips X 'Pert Pro MPD system with the CuKα radiation. The XRD measurements were carried out on powder samples at room temperature. Scanning Electron Microscope FEI Quanta FEG 250 using 30kV beam accelerating voltage with SE-ETD detector (secondary electron - Everhart-Thornley detector) working in high vacuum mode (pressure 10-4 Pa) was used to observed the structure of the glasses. SEM measurements were conducted on samples fractures with 7nm gold coating.
Detailed information can be found in: doi: 10.1016/j.proeng.2014.12.489