Electrical characterization of glass-ceramic sealant-metallic interconnect joined samples under solid oxide electrolysis cell conditions; influence on the microstructure and composition at the different polarized interfaces

In this study, the electrical resistivity of a glass-ceramic sealant is evaluated at 850 ◦C, for 2800 h under the applied voltage of 1.6 V. The glass-ceramic sealant is sandwiched between two Crofer22APU plates to produce Crofer22APU/Glass-ceramic/Crofer22APU samples. The Crofer22APU/glass-ceramic/Crofer22APU joints show electrical resistivity around 106-107 Ω cm, significantly high to ensure the insulation between two conductive interconnect plates. The detailed SEM-EDS post mortem analysis showed good thermo-mechanical compatibility of the glass-ceramic with the Crofer22APU substrates, thus excluding any detrimental interaction with the metallic interconnect under high applied voltage. XRD analysis of glass-ceramic confirmed the presence of crystalline phases with suitable CTEs, after electrical resistivity under harsh conditions.