The Particle-Size Dependence of the Activation Energy for Decomposition of Lithium Amide

Abstract

A question of size: LiNH2 decomposes into Li2NH and NH3 through two competing mechanisms, one that involves the formation of native defects in the interior of the material (by a Frenkel pair mechanism) and the other at the surface (see picture; H red, Li gray, N blue). The prevailing mechanism and hence the activation energy thus depend on the surface-to-volume ratio, or the specific surface area, which changes with the particle size.