Evaluation of La0.7Ca0.3Cr0.95Zn0.05O3–δ–Gd0.1Ce0.9O2–δ Dual-phase Material and its Potential Application in Oxygen Transport Membrane

In this work, a dual-phase material consisting of La0.7Ca0.3Cr0.95Zn0.05O3–δ (LCCZ, 40 wt%) and Gd0.1Ce0.9O2–δ (GDC, 60 wt%) was synthesized. Properties including phase structure, sintering behavior, electrical conductivity and oxygen permeability for LCCZ–GDC were evaluated. The results show that dense LCCZ–GDC dual-phase disks were obtained at the sintering temperature of 1250, 1300, 1350 and 1400 °C by tape casting and high temperature sintering method. The grain sizes of both GDC and LCCZ grew up with the increasing of sintering temperature. The average grain size of GDC was about 0.5, 0.8, 1.4, 1.8 μm while the average grain size of LCCZ was about 0.8, 1.5, 1.8 and 2 μm after sintering at 1250, 1300, 1350 and 1400 °C, respectively. Oxygen flux of LCCZ–GDC decreased with the increase of sintering temperature from 1250 to 1400 °C. The oxygen flux of LCCZ–GDC sintered at 1250 °C reached 0.079 mL/min/cm2 at 975 °C with a membrane thickness of 800 μm. Dual-phase material of LCCZ–GDC will be a promising oxygen transport membrane material for its low sintering temperature and good microstructure.