Abstract: A hydrogen-selective membrane including a metal leaf applied to a substrate. A system and method for fabricating a hydrogen-selective membrane, including applying a metal leaf to a substrate, annealing the metal leaf, applying a hydrogen-permeable metal to the annealed metal leaf on the substrate, and annealing the hydrogen-permeable metal and the annealed metal leaf to give an alloy of the hydrogen-permeable metal and the metal leaf. A system and method for repairing a hydrogen-selective membrane having defects including applying a metal leaf to an external surface of membrane material of the hydrogen-selective membrane, annealing the metal leaf and metal of the membrane material to form an alloy of the metal leaf and the metal to repair the defects.