ECS Transactions · 2013 · 11 citations · 0 references
Natural SciencesChemistryMaterials ScienceElectrochemical EngineeringElectrochemistrySpectroscopyCathode MaterialsElectrochemical CellsElectrochemical Impedance SpectroscopyElectrode MaterialsElectrode-electrolyte InterfacesImpedance SpectroscopyElectrochemical MeasurementsElectrode - Electrolyte InterphasesElectrode InterfacesEquivalent Circuit AnalysisIn Situ SpectroscopyPorous Electrode MaterialsSynchrotron X-ray CharacterizationX-ray Absorption Spectroscopy
Oxygen chemical potential distribution in a porous La 0.6 Sr 0.4 CoO 3- δ (LSC64) electrode on a Ce 0.9 Gd 0.1 CoO 1.95- δ (GDC) electrolyte under polarization was evaluated by using in situ X-ray absorption spectroscopy (XAS) at P (O 2 ) = 10 -2 bar and 873 K. The application of synchrotron X-ray focused into the submicrometer size enabled us to experimentally clarify the oxygen potential distribution in the vicinity of electrode/electrolyte interface with the position resolution of micrometer. Electrochemical impedance spectroscopy (EIS) measurements, followed by the analysis assuming the transmission line model (TLM) as an equivalent circuit, were performed with the same electrochemical cell for the XAS measurements. Based on the results by in-situ micro XAS and EIS measurements, the effective reaction area in the porous LSC64 electrode was discussed.