A method of making a composite gas separation module by providing a porous support material having deposited thereon a metal membrane layer, by imposing upon the surface of the metal membrane layer certain surface characteristics including an abrasion pattern and a relatively high surface roughness that provides for surface activation that enhances the placement thereon of a subsequent metal membrane layer without the use of a chemical activating solution. The composite gas separation module is useful in the separation of hydrogen from hydrogen-containing gas streams.