Fast Cu⁺ ion conducting phosphate iodide-glasses

The glass-forming region in the ternary system CuI-Cu₂O-P₂O₅, from which Cu²⁺ ion formation has been excluded, is described and compared with that in the corresponding Ag⁺-based system. The glasses are characterized by T_g values some 50°C higher than in the silver systems. Frequency independent (dc) conductivities along the join CuI+CuPO₃ have been determined over a wide range, and found to be characterized by both higher activation energies and pre-exponential constants than the silv{approaches the limit}r glasses. The combination leads to higher conductivities in the Cu⁺-based glasses in the composition range 20-30 mole% CuI at room temperature and above.