The crystallization and FTIR spectra of ZrO2-doped 36Fe2O3–10B2O3–54P2O5 glasses and crystalline compounds

• IBP glass with less than 6 mol% Zr mainly crystallize Fe4(PO4)2O, Fe2(PO4)O at 850 °C.
• ZrP2O7 appears when IBP glass doped with more than 6 mol% ZrO2.
• ZrO2 restrains Fe4(PO4)2O, Fe2(PO4)O crystallized from the ZrO2-doped IBP glasses.
• PO3− and PO43− groups gradually transform into P2O74− groups with ZrO2 increasing.

The crystallization and structure of ZrO2-doped 36Fe2O3–10B2O3–54P2O5 glasses and crystalline compounds are studied by using X-ray diffraction and FTIR spectroscopy, respectively. It is found that the main crystallization is Fe4(PO4)2O, Fe2(PO4)O when 36Fe2O3–10B2O3–54P2O5 glass with less than 6 mol% of ZrO2 is heated at 850 °C. When the doped ZrO2 is larger than 6 mol% (including 6 mol%), ZrP2O7 crystallization appear. Furthermore, their crystallization behaviors suggest that ZrO2 can promote ZrP2O7 crystallized from the ZrO2-doped 36Fe2O3–10B2O3–54P2O5 glass and restrain Fe4(PO4)2O and Fe2(PO4)O crystallization formed due to the PO3− groups and PO43− phosphate groups gradually transforming into pyrophosphate P2O74− groups with increasing content of ZrO2. The knowledge provides an improved understanding of the role of Zr in the structure of iron borophosphate glasses and its crystalline compounds.