Asymmetric layered vanadium membranes for hydrogen separation

Asymmetric Pd/V/Ni alloy membranes have been fabricated with varying Ni thickness, and hydrogen permeance has been examined over a wide range of pressures and temperatures. Hydrogen permeance increases with decreasing Ni thickness, down to a limiting thickness of 150 nm, beyond which permeance degraded due to incomplete Ni coverage. The permeance was 65% that of a symmetrical Pd/V/Pd membrane with 500 nm Pd layers. The cost-effectiveness is dependent on raw Pd price and manufacturing costs.