Encapsulation can also narrow the size distribution of core particles. The onset of encapsulation is determined by reaction conditions, which can be manipulated to ensure that the particles are the correct size. An additional benefit is that the encapsulation protects the primary particles from atmospheric exposure, preventing oxygen impurities and improving material quality. The figure to the left is a transmission electron micrograph of a salt coated particle of nanoscale titanium. The dark particles are titanium and the lighter coating is salt.
Sodium chloride is an ideal encapsulation material.
The Advanced Powder Synthesis Laboratory is directed by Professor Richard L. Axelbaum.