Why gold-palladium alloys are better than palladium for hydrogen storage

(Institute of Industrial Science, The University of Tokyo) A research team led by The University of Tokyo investigated why alloying with gold improves hydrogen storage in palladium. The hydrogen concentration in sub-surface palladium was maximized when 0.4 monolayers of gold atoms were alloyed in the surface. DFT calculations and photoemission spectroscopy showed that gold destabilized the surface-chemisorbed hydrogen atoms, hastening their diffusion from the surface into the interior. This will aid the design of hydrogen storage materials as energy carriers and catalysts.