Coupling of tape casting and in situ solid-state reaction for manufacturing La0.9Sr0.1Ga0.8Mg0.2O3 electrolyte of efficient solid oxide cells

Abstract

Perovskite oxide La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM) is an intermedium-temperature solid oxide cell electrolyte material with extraordinary oxygen-ion conductivity. However, the manufacturing procedures of LSGM discs are complex involving multiple steps of powder preparation, forming, and sintering at high temperatures. Herein, thin LSGM electrolyte discs are prepared by coupling of tape casting and in situ solid-state reaction using oxides/carbonates as the feedstock. A pure-phase LSGM electrolyte disc with uniform elemental distribution is obtained by sintering at 1450 °C, and it possesses an ionic conductivity of 0.105 S cm1 at 800 °C, a thermal expansion coefficient of 12.2 × 106 K1, and a bending strength of 156 MPa A 170 µm thick LSGM electrolyte-supported single cell delivers a peak power density of 0.96 W cm2 at 800 °C and an electrolysis current density of 1.82 A cm2 at 1.5 V with no noticeable degradation for 200 h. The findings of this research provide a cost-effective approach for manufacturing the LSGM electrolytes of efficient and durable solid oxide cells.