Raman and Mossbauer studies of iron phosphate-silicate glasses

The present paper analyzes the impact of incorporation of various amounts of Fe2O3 into phosphate-silicate glasses. Amorphous solids in the P2O5-SiO2-K2O-MgO-CaO system with constant molar ratio of P2O5 and SiO2 as 41: 6 and 0 divided by 30 mol.% iron oxide addition were successfully obtained. Fe2O3 was incorporated at the expense of CaO and MgO. Materials were subjected to Raman and Mossbauer studies in order to analyze their structure. Transformation between glasses with low Fe2O3 addition and samples containing more than 4 mol.% iron ions was reflected on Raman and Mossbauer spectra. Diverse valent states and coordination of iron ions manifested themselves in results of Mossbauer study. The role of iron ions as network modifiers and formers was also implied. The performed study constitutes an invaluable basis for further analysis of the obtained materials, whereas the provided methods can be applied for many challenging projects, hence making them a scientific novelty. (C) 2018 Elsevier B.V. All rights reserved.