A membrane includes a metal or coordination complex that selectively interacts with one or more materials. The membrane can be used for facilitated transport separation of the materials. The metal complex can include any suitable metal center, but preferably includes a late transition metal. The metal complex can also include any suitable ligand, but preferably includes a triphosphacyclononane. The metal complex can be covalently linked to the membrane.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with government support under Contract No. DE-AC07-05-ID14517, awarded by the U.S. Department of Energy. The U.S. government has certain rights in the invention.