In this work, hydrogen permeation properties of Ni-La0.5Ce0.5O2-delta (LDC) asymmetrical cermet membrane are investigated, including hydrogen fluxes (JH(2)) under different hydrogen partial pressures, the influence of water vapor on JH(2) and the long-term stability of the membrane operating under the containing-My atmosphere. Ni-LDC asymmetrical membrane shows the best hydrogen permeability among LDC-based hydrogen separation membranes, inferior to Ni-BaZr0.1Ce0.7Y0.2O3-delta asymmetrical membrane. The water vapor in feed gas is beneficial to hydrogen transport process, which promote an increase of JH(2) from 5.64 x 10(-8) to 6.83 x 10(-8) mol cm(-2) s(-1) at 900 degrees 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. (C) 2015 Elsevier B.V. All rights reserved.