Preparation and characterization of high temperature Sr(Ce_0.6Zr_0.4)_0.9Y_0.1O_3-δ/YBaCo₂O_5+δ mixed proton-electron composite membrane

In this study, the various Sr(Ce_0.6Zr_0.4)_0.9Y_0.1O_3-δ/YBaCo₂O_5+δ (SCZY/YBCO) composite ceramic membranes were prepared by sintering at different temperatures and used as proton membranes for hydrogen permeation. SCZY and YBCO powders were prepared by the citrate-ethylenediaminetetraacetic acid sol-gel process and solid-state reaction method, respectively. The chemical reaction, structure, morphology, thermal expansion, and electrical conductivity of SCZY/YBCO were investigated through X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermal mechanical analyzer (TMA) and direct current four-probe method. The relative sintered density of SCZY/YBCO membrane sintered at 1250 °C was as high as 99.5%. The conductivity of the SCZY/YBCO increased with the sintering temperature. The SCZY/YBCO sample sintered at 1250 °C exhibited the highest conductivity of 13.44 S/cm at 800 °C. The H₂ permeability of the SCZY/YBCO membrane was 3.83 mL min⁻¹ cm⁻², much higher than that of SCZY at 800 °C (1.37 mL min⁻¹ cm⁻²).