Electrophoretic deposition of (Mn,Co)3O4 spinel coating for solid oxide fuel cell interconnects

We discuss here our attempt to develop (Mn,Co)(3)O-4 spinel coatings on the surface of Cr-containing steel through electrophoretic deposition (EPD) followed by reduced-atmosphere sintering for solid oxide fuel cell (SOFC) interconnect application. The effects of EPD voltages and sintering atmospheres on the microstructure. electrical conductivity and long-term stability of the coated interconnects are examined by means of scanning electron microscopy (SEM). energy dispersion spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), and four-probe resistance techniques. For the spine! coatings generated using smaller voltage than 400 V. the interconnect surfaces exhibit good packing behavior and high conductivity. The reduced atmosphere during sintering has a beneficial impact on the minimizing chromia subscale formation and thus reducing the area specific resistance (ASR) of the coated interconnects. Moreover, it is interesting to note that a more stable long-term performance is achieved for the spinel coating sintered in H-2/H2O atmosphere with thin chromia sub-scale and no Cr penetration. Based on the current results. EPD followed by reduced-atmosphere sintering is a fast and economic way to deposit (Mn,Co)(3)O-4 coating for SOFC interconnect applications. (C) 2011 Elsevier B.V. All rights reserved.