Observation of single colloidal platinum nanocrystal growth trajectories.
Understanding of colloidal nanocrystal growth mechanisms is essential for the syntheses of nanocrystals with desired physical properties. The classical model for the growth of monodisperse nanocrystals assumes a discrete nucleation stage followed by growth via monomer attachment, but has overlooked particle-particle interactions. Recent studies have suggested that interactions between particles play an important role. Using in situ transmission electron microscopy, we show that platinum nanocrystals can grow either by monomer attachment from solution or by particle coalescence. Through the combination of these two processes, an initially broad size distribution can spontaneously narrow into a nearly monodisperse distribution. We suggest that colloidal nanocrystals take different pathways of growth based on their size- and morphology-dependent internal energies.
Zheng
Haimei
H
National Center for Electron Microcopy, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Smith
Rachel K
RK
Jun
Young-Wook
YW
Kisielowski
Christian
C
Dahmen
Ulrich
U
Alivisatos
A Paul
AP