In situ TEM observation of the nucleation and growth of silver oxide nanoparticles.

The nucleation, growth, and coalescence of silver oxide nanoparticles have been investigated dynamically and at high spatial resolution by using the electron beam of a transmission electron microscope to stimulate and to observe the processes. Under the assumption the particles are hemispherical, the growth rate was found to be proportional to the square root of the electron irradiation time. This result suggests that the rate-limiting step is the attachment of atoms to the nanoparticles. Growth of the nanoparticles occurred by the addition of columns of atoms on {111} planes. Particle impingement resulted in interpenetration of the particles and, ultimately, the formation of a grain boundary.