The Kirkendall eff ect is a classical phenomenon in materials science, and it is referred to as a nonreciprocal interdiff usion process through an interface of two metals with strikingly diff erent atomic diff usivities, leading to a formation of vacancies called Kirkendall voids. The nanoscale Kirkendall eff ect has been vastly applied in the fabrication of hollow nanostructures after the fi rst report on the synthesis of Co-based hollow nanocrystals. In this Feature Article, we briefl y start with an introduction on the Kirkendall effect concept, followed by the general synthetic strategy toward the production of hollow Kirkendall voids. The overall synthetic strategies are based on the design of diff usion couples at the nanoscale, and then, we discuss the factors that govern the formation of Kirkendall voids at the nanoscale, from the viewpoint of the nanoparticle size, nanoparticle crystallinity, and nanoparticle environment. We conclude with a summary and perspectives on the design of hollow nanostructures governed by the Kirkendall effect.
Source : Nano Kirkendall Effect Related to Nanocrystallinity of Metal Nanocrystals: Influence of the Outward and Inward Atomic Diffusion on the Final Nanoparticle Structure
ZYang, N. Yang and M.P.Pileni J.Phys.Chem.C., 2015,119, 22249-22260