Sol-Gel Synthesis and Characterization of SiO2—P2O5—ZrO2

Zirconia phosphosilicates were prepared by the sol-gel method using tetraethylorthosilicate, triethyl phosphate, and zirconium n-propoxide. Monolithic, transparent gels were formed with 10 mole% ZrO₂, and 10, 20 or 30 mole% P₂O₅. The influence of the mole% P₂O₅, treatment temperature and water content, on thermal behavior, water adsorption, and proton conductivity were studied. A heat treatment at 200°C was effective in removal of residual organics, creating a porous material capable of good water retention upon rehydration.