Chemical durability and structure of zinc–iron phosphate glasses

• Published in: Journal of non-crystalline solids Vol. 292; no. 1; pp. 150 - 157
• Main Authors: Reis, S.T, Karabulut, M, Day, D.E
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.11.2001; Elsevier
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Chemical industry and chemicals; Exact sciences and technology; Glasses; Structure, analysis, properties; P145; C160; S440; Fourier transformation; Chemical stability; Differential thermal analysis; Moessbauer spectrometry; Zinc Oxides; Phosphate glass; Density; X ray diffraction; Dissolution; Physical properties; Infrared spectrometry; Iron Oxides; Local structure; Phosphorus Oxides; Property structure relationship; Chemical properties; Amorphous state structure
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/S0022-3093(01)00880-8

The chemical durability of zinc–iron phosphate glasses with the general composition (40− x)ZnO– xFe 2O 3–60P 2O 5 has been measured. The chemical durability and density of these glasses increase with increasing Fe 2O 3 content. Glasses containing more than 30 mol% Fe 2O 3 had an excellent chemical durability. The dissolution rate (DR), calculated from the weight loss in distilled water at 90 °C for up to 32 days, was ∼ 10 −9 g/ cm 2/ min which is 100 times lower than that of window glass and 300 times lower than that of a barium ferro, aluminoborate glass. The structure and valence states of the iron ions in these glasses were investigated using Mössbauer spectroscopy, X-ray diffraction, infrared spectroscopy and differential thermal analysis. X-ray diffraction indicates that the local structure of the zinc–iron phosphate is related to the short range structures of crystalline Zn 2P 2O 7, Fe 3(P 2O 7) 2 and Fe(PO 3) 3. Both Fe(II) and Fe(III) ions are present in all of these glasses. The presence of an Fe–O–P related band in the infrared (IR) spectra of the glasses containing more than 30 mol% Fe 2O 3 is consistent with their excellent chemical durability.