Air stability and magnetic properties of GdN, TiN, and (Gd,Ti)N nanoparticles

摘要

GdN, TiN, and (Gd,Ti)N nanoparticles were prepared by arc evaporating Gd, Ti, and Gd-Ti alloys in N2, respectively. Most of these nanoparticles show narrow size distribution with average diameter of 20 nm. Shell/core structure was observed in the (Gd,Ti)N nanoparticles, in which the shell was formed by surface reaction with air. (Gd,Ti)N nanoparticles are more stable than GdN nanoparticles in air due partially to the formation of the protective shell. The Curie temperature of GdN nanoparticles is lower than that of the bulk GdN. Both GdN and (Gd, Ti)N nanoparticles are difficult to reach magnetic saturation and show zero coercivity.