Applying multifunctional perovskite LaNiO3 as electrolyte and anode for low‐temperature solid oxide fuel cell

Recently, due to the unique advantage in ionic conductivity, semiconductor–ionic conductor composite (SIC) has been widely applied as electrolyte for solid oxide fuel cell (SOFC), and the suitable anode and cathode should be chosen to match the SIC electrolyte. Inspired by this ideology, the semiconductor lanthanum nitrate (LaNiO3) with perovskite structure was prepared by sol-gel method and then composed with ionic conductor yttrium-stabilized zirconia (YSZ) to form LaNiO3-YSZ SIC, which was applied as electrolyte membrane, simultaneously the Li2CO3–LaNiO3 composite and Ni0.8Co0.15Al0.05LiO2 (NCAL) were respectively utilized as anode and cathode for fuel cell construction. Through optimizing the electrolyte composition, such device based on LaNiO3-YSZ electrolyte and Li2CO3–LaNiO3 anode received a supreme performance of 505 mW/cm2 at 550 °C, and the maximum power density can also maintain at 350 mW/cm2 even as the temperature dropped to 475 °C. The excellent performance is attributed to the decent ionic conductivity of LaNiO3-YSZ electrolyte and the outstanding catalysis activity of electrodes. In addition, we have found that the addition of Li2CO3 component into anode can substantially enhance the cell performance. Our result demonstrates that the multifunctional LaNiO3 can be simultaneously applied as electrolyte and anode for low-temperature SOFC.