An Oxide Ion and Proton Co-Ion Conducting Sn[sub 0.9]In[sub 0.1]P[sub 2]O[sub 7] Electrolyte for Intermediate-Temperature Fuel Cells

The ionic conductivity of ceramic was investigated under various atmospheres within the temperature range of . Similar to mixed-conductive perovskite oxides at high temperatures (such as at ), can conduct both protons and oxide ions at low temperatures . The conductivity of reaches at in wet nitrogen. Its transport numbers determined by steam concentration cells are around 0.76 for a proton and 0.12 for an oxide ion. The performance of direct methanol fuel cells at using mixed-ion conductive electrolyte is higher than that at using pure proton conductive electrolyte. This is attributed to direct oxidation of CO at the anode by the oxide ions generated at the cathode and moved through the electrolyte.