Dense Pd/TiO2/Ti-Al alloy composite membranes on porous Ti-Al alloy supports were prepared by electroless plating. The TiO2 membrane was applied as an inter-diffusion barrier between the Pd layer and the Ti-Al alloy support to prevent intermetallic diffusion. Electron probe microanalysis (EPMA) and EDX cross-sectional line scans showed that the intermediate layer was effective as the diffusion barrier for Pd membranes on Ti-Al alloy supports after 40 h of treatment at 973 K in pure hydrogen. The thickness of the resulting Pd composite membrane was approximately 14 mu m. The hydrogen permeance through the Pd composite membrane was 1.07 x 10(-3) mol m(-2) s(-1) Pa-0.5 at 773 K. The permeance and selectivity of the Pd composite membrane were measured at different temperatures and pressures. The permeance tests showed that the Pd/TiO2/Ti-Al alloy composite membranes have high H-2/N-2 selectivity. In addition, heat cycles indicated that the structure of the Pd composite membranes was stable. (C) 2011 Elsevier B.V. All rights reserved.