Intermediate temperature CO₂ electrolysis by using La_0.9Sr_0.1Ga_0.8Mg_0.2O₃ oxide ion conductor

Solid oxide electrolysis cell for electrolysis of CO₂ to CO was studied with the cell using LaGaO₃-based electrolyte at the intermediate temperature (i.e. 973-1 173 K). Various metal additives to Ni were examined for cathode to CO₂ reduction and it was fund that Ni added with Fe shows high activity and the current density of 1.5 A/cm² was achieved at 1.6 V and 1 073 K on Ni-Fe (9:1) cathode. Improved electrolysis activity was explained by the expanded reaction site which may be assigned the fine particle of Ni. Furthermore, effects of additives to Ni cathode were studied and it was found that the electrolysis current could be much improved by addition of Fe to Ni. Effects of oxide ion conductor mixing with Ni-Fe were further studied and it was found that mixing La_0.6Sr_0.4Fe_0.9Mn0.₁O₃ with Ni-Fe bimetal is the most effective for achieving high electrolysis current of CO₂ of 2.07 A/cm² at 1.6 V and 1 073 K.