A high stability Ni–La0.5Ce0.5O2−δ asymmetrical metal-ceramic membrane for hydrogen separation and generation

• Ni-LDC asymmetric cermet membrane was prepared by a simple method.
• The membrane showed the best permeability among LDC-based membranes.
• Hydrogen separation and generation could be realized using the Ni-LDC membrane.
• JH2 remained stable whether operating in CO2 condition or dual-function mode.

In this work, hydrogen permeation properties of Ni–La0.5Ce0.5O2−δ (LDC) asymmetrical cermet membrane are investigated, including hydrogen fluxes (JH2) under different hydrogen partial pressures, the influence of water vapor on JH2 and the long-term stability of the membrane operating under the containing-CO2 atmosphere. Ni-LDC asymmetrical membrane shows the best hydrogen permeability among LDC-based hydrogen separation membranes, inferior to Ni–BaZr0.1Ce0.7Y0.2O3−δ asymmetrical membrane. The water vapor in feed gas is beneficial to hydrogen transport process, which promote an increase of JH2 from 5.64 × 10−8 to 6.83 × 10−8 mol cm−2 s−1 at 900 °C. Stability testing of hydrogen permeation suggests that Ni-LDC membrane remains stable against CO2. A dual function of combining hydrogen separation and generation can be realized by humidifying the sweep gas and enhance the hydrogen output by 1.0–1.5 times. Ni-LDC membrane exhibits desirable performance and durability in dual-function mode. Morphologies and phase structures of the membrane after tests are also characterized by SEM and XRD.