Understanding the effect of oxide components on proton mobility in phosphate glasses using a statical analysis approach

The models to describe the proton mobility (μ(H)) together with the glass transition temperature (T(g)) of proton conducting phosphate glasses employing the glass composition as descriptors have been developed using a statical analysis approach. According to the models, the effects of additional HO(1/2), MgO, BaO, LaO(3/2), WO(3), NbO(5/2), BO(3/2) and GeO(2) as alternative to PO(5/2) were found as following. μ(H) at T(g) is determined first by concentrations of HO(1/2) and PO(5/2), and μ(H) at T(g) increases with increasing HO(1/2) concentration and decreasing PO(5/2). The component oxides are categorized into three groups according to the effects on μ(H) at T(g) and T(g). The group 1 oxides increase μ(H) at T(g) and decrease T(g), and HO(1/2), MgO, BaO and LaO(3/2) and BO(3/2) are involved in this group. The group 2 oxides increase both μ(H) at T(g) and T(g), and WO(3) and GeO(2) are involved in this group. The group 3 oxides increase T(g) but do not vary μ(H) at T(g). Only NbO(5/2) falls into the group 3 among the oxides examined in this study. The origin of the effect of respective oxide groups on μ(H) at T(g) and T(g) were discussed.