Fabrication of fuel electrode supported proton conducting SOFC via EPD of La2Ce2O7 electrolyte and its performance evaluation

Abstract

The proton conducting La2Ce2O7 electrolyte has already been shown to be chemically more stable to H2O and CO2 than BaCeO3 based electrolyte materials. It has become widely popular as an alternative electrolyte for low to intermediate temperature operation in solid oxide fuel cells. Few initial studies have reported the fabrication of LCO-based fuel cells using the co-pressing process. Here, we present an alternative, simple, cost-effective and efficient method for the deposition of uniform and dense La2Ce2O7 electrolyte coatings, which is a key requirement for any fuel cell fabrication process. In this work, La2Ce2O7 is synthesized by a conventional solid state reaction route and we have established the process of fuel cell fabrication followed by its investigation for SOFC application as electrolyte material. Different alcohols (e.g. butanol, ethanol, acetone, acetyl acetone and isopropanol) are used as dispersion medium, the suspension chemistry and subsequent coating of LCO powders by electrophoretic deposition are investigated. A thin and good quality coating of about 11 μm thickness is obtained in an ethanol-based suspension under deposition conditions at 50 V for 2 min. Fuel electrode supported half cells with LCO electrolyte fabricated by electrophoretic deposition and performance test of fabricated cell is evaluated in moist H2 (∼3% H2O) as reducing medium and static air as oxidizing medium.