When
Ligand Exchange Leads to Ion Exchange: Nanocrystal
Facets Dictate the Outcome
Indika
K. Hewavitharana
Stephanie L. Brock
10.1021/acsnano.7b05534.s001
https://acs.figshare.com/articles/journal_contribution/When_Ligand_Exchange_Leads_to_Ion_Exchange_Nanocrystal_Facets_Dictate_the_Outcome/5563051
This
study demonstrates that ligand exchange of nanocrystals (NCs)
is not always an innocuous process, but can lead to facile (room temperature)
ion exchange, depending on the surface crystal faceting. Rock salt
PbTe NCs prepared as cubes with neutral facets undergo room-temperature
ligand exchange with sulfide ions, whereas cuboctahedron-shaped particles
with neutral {100} and polar {111} facets are transformed to PbS,
driven by ion exchange along the ⟨111⟩ direction. Likewise,
cation exchange (with Ag<sup>+</sup>) occurs rapidly for cuboctahedra,
whereas cubes remain inert. This dramatic difference is attributed
to the relative surface area of {111} facets that promote rapid ion
exchange and shows how facet engineering is a powerful knob for the
control of reaction pathways in nanoparticles.
2017-10-16 00:00:00
rock salt PbTe NCs
ion exchange
Nanocrystal Facets Dictate
room-temperature ligand exchange
surface crystal faceting