Nano-engineering of magnesium hydride for hydrogen storage

The destabilization of magnesium hydride (MgH 2) by solid-state reaction with Si in a nanoscale under vacuum was studied. The nanostructured Si films were deposited on the nanocrystalline MgH 2/Mg composite substrate by the pulsed laser deposition (PLD). The cross-sectional transmission electron microscopy (TEM) shows that the metastable Mg 5Si 6 is the only intermetallic compound formed in the Si–Mg region during the deposition. The destabilization of MgH 2 by Si forming the Mg 2Si intermetallic compound was not observed in a nanoscale at 150 °C under vacuum.