| Abstract Scope |
Due to their unique and tunable properties, metallic nanoparticles are utilized in a growing number of applications. Recrystallization, which is a primary method for manipulating the properties of bulk metals, has not yet been applied to individual metal nanoparticles. We studied pristine, single crystal platinum nanoparticles during a recrystallization annealing after deformation. We found that deformation causes a dramatic change in particles orientation, misaligning them by up to 28 degrees with respect to their stable orientation. During the recrystallization annealing the particles exhibited many different behaviors - exposing thermodynamically unfavored facets, breaking apart, coalescing, or forming holes and turning into donut-like structures. Microstructurally, nucleation of new grains was observed, but in the smallest particles these new grains were quickly absorbed back into the deformed matrix. We found a strong correlation between the particles size, imposed plastic strain, and their annealing behavior, and discussed these observations in terms of phenomenological kinetic model. |