Effect of carbon addition on hydrogen storage performances of magnesium-based alloys: From bulk powders to thin films

Mg-based thin films were successfully grown by Pulsed Laser Deposition. Dramatic optical changes were observed depending on the conditions of deposition. Films grown in vacuum were shiny metallic whereas the ones grown in a Ar/H 2 gas mixture were highly transparent. Ex situ hydrogenation, by annealing the films at 200 °C in 15 bars of hydrogen, led to similar metallictransparent transformation. Mg-C x (x ≤ 20 %) films show a faster hydrogenation associated with a significant decrease in oxygen content by carbon addition.