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The performance of solid oxide fuel cells (SOFCs) can be degraded by ''chromium poisoning'' where thermally grown Cr 2 O 3 on metallic surfaces forms volatile Cr-containing species that are redeposited on active regions of the cathode. This phenomenon is further exacerbated for porous metallic interconnects and metal-supported electrodes due to their large surface-to-volume ratios. In this study, electrophoretic deposition (EPD) of CuNi 0.2 Mn 1.8 O 4 spinel powders on porous SUS430 metallic substrates using alternating current (AC) was explored. Two-step densification heat treatment was used to form a thin, uniform, protective spinel coating. The area-specific resistance (ASR) and weight gain were tracked during 100-h oxidation tests at 700°C in air. The results showed that, despite the considerable complexity of the sample shape, AC EPD was able to form a protective coating layer that significantly limited the growth rate of the thermally grown oxide (TGO) by reducing the k g value by a factor of 25.

Chromium poisoning of the cathode remains a significant obstacle to the stable long-term performance of solid oxide fuel cells. This study reports, a quick, in-situ mitigation method, called electrochemical cleaning. By applying a mild anodic bias, the electrochemical deposition reactions of chromium-containing species are reversed. Chromium vapor species are formed, freeing active electrochemical sites in the air electrode. An LSM/YSZ-based cell was exposed to Cr vapors at 800ºC and then subjected to electrochemical cleaning. Cell performance recovery was evidenced by current-voltage and EIS measurements. Chromium removal was verified using SEM and EDS analyses. The cyclability of the electrochemical cleaning was tested by repeated poisoning and cleaning of another cell. Investigation into the effect of cell operating parameters (current density and cell temperature) on the rate of cleaning is discussed.