Size dependence of air oxidation for Mg nanoparticle

Abstract

The size dependence of the air oxidation for Mg nanoparticles is studied by Mg K-edge NEXAFS and AFM techniques. In the case of the exposure to the air for 3 days, the degree of the air oxidation for Mg nanoparticles increases with reduction of the size of Mg nanoparticle. However, the opposite size dependence is observed in the case of the exposure to the air for 25 days, i.e. the air oxidation reaction for the smaller Mg nanoparticles is more inhibited in the case of long term exposure to the air. This size dependence is attributed to the occupation of the free spaces between Mg nanoparticles, which protects against the incursion of the air component molecules into the multilayer of Mg nanoparticles. © 2011 The Surface Science Society of Japan.