Vanadium v oxide

The base phosphate glasses were prepared by melting. The chemical compositions of the studied phosphate glasses in Mol% are shown in Table 1. The glass compositions formulated using NaH 2 PO 4 99.0% Sigma, calcium carbonate (CaCO 3 ) 99% Sigma aldrich, Phosphorus pentoxide (P 2 O 5 ) 99% Sigma Aldrich and Vanadium(V) oxide (V 2 O 5 ) 99.6% Aldrich and Molybdenum(IV) oxide (MoO2) 99% Aldrich. The precursors were weighed to satisfy the proposed glass formulations and placed into a 200ml platinum crucible. Care was taken while weighing Phosphorus pentoxide in order to avoid moisture content. The crucible is placed into a furnace at temperature 750-1200 o C for 1h according to the melting point of the glass batches.
The molten glasses were then poured into a preheated graphite molds in order to design glass blocks by casting. The glass blocks were annealed at the right annealing temperature according to the results of thermal analysis, at 350 o C/1h, and then allowed to cool to room temperature, in order to remove the residual stresses in the glass. The glass rods were obtained and cut into 12 mm diameter, 2 mm thick discs using a diamond saw.