Structural studies of phosphate glasses with high ionic conductivity

Lithium phosphate glasses with different chemical composition have been studied using infrared absorption spectroscopy (FTIR) and photoelectron spectroscopy (XPS). FTIR and XPS spectra were analyzed to determine the main structural units present in the glass. Absorption bands were identified and assigned to appropriate bond vibrations. It has been shown that analyzed glasses are built up mainly of short chains and rings consisting of metaphosphate structural units – Q2. Some pyro- and orthophosphate units Q1 and Q0, respectively are also present. Photoelectron spectroscopy studies have revealed that titanium exists in two valence states: as Ti3+ and Ti4+. Increasing TiO2 content results in shortening of P–O bonds but leads to elongation of PO bonds in PO4 tetrahedra.