Electrophoretic deposition and low-temperature densification of Cu1.35Mn1.65O4 spinel for an interconnect protective coating in solid oxide fuel cells

摘要

As a protective coating of the interconnects in solid oxide fuel cells, spinel-structured Cu1.35Mn1.65O4 powder was coated onto 460FC stainless steel by using the electrophoretic deposition method. A suitable amount of iodine was added to ethanol to charge the spinel powder with a high zeta potential value. Stainless steel substrates were immersed in a slurry, and a DC voltage in the range of 20-60 V was applied for 30-120 s. Because a low-temperature densification of the coated film is crucial for minimizing Cr out-diffusion from the stainless steel substrate, the coated spinel was decomposed into Cu and MnO by applying a heat treatment at 800 degrees C in a 5 H-2/95 N-2 atmosphere. Then, it was oxidized at 700 degrees C in air, leading to appropriate densification. The area-specific resistance of the films was 15-29 m Omega cm(2) after 1000 h at 700 degrees C in air. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.