Influence of Ti on the formation and stability of gas-phase Mg nanoparticles

The effect of titanium on magnesium nanoparticle formation is investigated in relation to the importance of Mg in hydrogen storage. Addition of Ti reduces the Mg-nanoparticle sizes in the range of 5-20 nm and leads to less protective Mg-oxide shells. This in return accelerates the evaporation of Mg that leads to hollow Mg cores. The presence of oxygen plays a dual role in forming MgO protected stable Mg nanoparticles above a critical size (similar to 15 nm) and hollow ones below this size both due to evaporation and oxidation associated Kirkendall effects. (C) 2010 American Institute of Physics. [doi:10.1063/1.3533812]