Raman and FTIR spectra of modified iron phosphate glasses containing arsenic

• Arsenic has great solubility and compatibility with modified iron phosphate glass.
• Addition of As2O3 to the modified iron phosphate glass leads to the conversion of Q1 to Q2.
• Arsenic is incorporated into the phosphate network in the form of P–O–As bonds.

The structural properties of 20CaO–8B2O3–24Fe2O3–48P2O5 + xAs2O3 (x = 0, 1, 5, 10, 15 mol%) glasses have been investigated by X-ray diffraction (XRD), transmission electron microscope (TEM), Raman and Fourier transform infrared spectrum (FTIR), differential thermal analysis (DTA). The XRD and TEM analysis indicates great solubility of arsenic in the modified iron phosphate melts. The Raman and FTIR spectra show that with increasing As2O3 content in glass compositions, the phosphate chains get less depolymerised, resulting in conversion of Q1 to Q2. As takes part network-forming positions and results in the PO2 units interacting with As2O3 and forming P−O−As linkages/bridges. The higher (Tr–Tg) suggests the thermal stability is improved with the addition of As2O3.