Water resistance of cerium phosphate glasses as studied by in situ high temperature IR microspectroscopy

In order to study water resistance of cerium phosphate (CeP) glasses, behavior of infrared (IR) bands of the CeP glass was investigated by using high temperature IR microspectroscopy. A small sharp 2165 cm− 1 band is observed in both Raman and IR spectra only for the phosphate glass containing Ce and is considered to be due to combination of symmetric stretching vibration of PO (1185 cm− 1) and asymmetric stretching vibration of POH (980 cm− 1) bonds of Q2 species, based mainly on the similarity of reversible heating behavior of the IR bands. The 3085 cm− 1 band can correspond to OH stretching vibrations of POH species associated with Q2 species. The broad band around 3500 cm− 1 appeared after the water treatment of the CeP glass. This band can be due to H2O molecules H bonded to POH species of the Q2 units and was mostly lost upon heating. Origins of water resistant properties of the CeP glass were therefore considered to be due to strong Q2 PO chains with POH bonds.