Hydrogen transport properties of palladium film prepared by colloidal spray deposition

Palladium films were fabricated by a novel colloidal spray deposition method. Dense, crack-free Pd films with thickness of 5–11 μm were successfully fabricated on porous yttria-stabilized zirconia (YSZ) substrates having pore size of 3–7 μm. Scanning electron microscopy showed that the film has uniform thickness and is well bonded to the substrate. The surface of the Pd film is composed of well-crystallized plate-like grains with diameter of 2–4 μm and has a rough texture. The X-ray diffraction pattern of the as-sintered Pd film indicates (111) preferred crystal orientation. The hydrogen permeation properties of the films were investigated at temperatures of 330–530 °C using 90% H2/balance He and N2 as feed and sweep gases, respectively. The hydrogen permeation of the supported Pd films with thickness of 5–11 μm was limited by both the diffusion of hydrogen through the metal bulk and the gas-phase transport through the support. The resistance of the gas-phase transport through the substrate was lowered significantly by reducing the thickness of the substrate.