Realizing stable high hydrogen permeation flux through BaCo0.4Fe0.4Zr0.1Y0.1O3-δ membrane using a thin Pd film protection strategy

Hydrogen (H-2)-selective membrane is an enabling technology for high purity H-2 production from natural gas. Here, we demonstrate the feasibility to apply BaCo0.4Fe0.4Zr0.1Y0.1O3-delta (BCFZY), a widely studied MPEC composition with high electronic conductivity as H-2 permeation membrane by sputtering thin Palladium (Pd) films on its feed and permeate surfaces as a protective layer to prevent BCFZY reduction upon long-term exposure to reducing H-2. Pd thin film also acts as a catalytic layer to enhance H-2 dissociation in the feed surface and H association in the permeate surface. Pd-sputtered BCFZY (Pd vertical bar BCFZY vertical bar Pd) membrane displayed exceptionally high H-2 flux that varies from 0.101 rise to 0.213 mL min(-1) cm(-2) (450 degrees C-650 degrees C) under the 10% H-2-90% N-2/Argon (Ar) gradient. The attainment of significant H-2 permeability below 500 degrees C shown here indicates the possibility to lower the operating temperature for H-2 permeation using MPEC materials. Pd vertical bar BCFZY vertical bar Pd membrane also demonstrated stable, high H-2 flux that fluctuates more or less 0.138 mL min(-1) cm(-2) during the continuous operation over 225-h duration.