Palladium nanoneedle “highways” for fast hydrogen transport in magnesium nanoparticle assembled films

The importance of hydrogen storage for mobile applications remains a timely subject with respect to a sustainable energy economy. Magnesium is a viable material for hydrogen storage by insertion, because of its low weight, abundance, and non-toxicity. A major obstacle for magnesium hydrides to be used for hydrogen storage is the high temperature for release, making it impracticable. However, nanoscale magnesium shows promising hydrogen desorption temperatures, which is employed in the form of nanoparticles in this work. A palladium "nanoneedle" network was used to speed up hydrogen transport to and from the magnesium nanoparticles in a matter of minutes. By using the optical changes that accompany the presence of hydrogen in magnesium, hydrogen transport was studied. The palladium nanoneedle "highways" improved the (de-) hydrogenation of magnesium nanoparticles by at least a factor two, which could be a template for further improvements in hydrogen storage systems.