ja2097964_si_003.avi (2.53 MB)
Nanoreactors for Studying Single Nanoparticle Coarsening
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posted on 2012-01-11, 00:00 authored by Jinan Chai, Xing Liao, Louise R. Giam, Chad A. MirkinThe ability to observe intermediate structures as part
of coarsening
processes that lead to the formation of single nanoparticles (NPs)
is important in gaining fundamental insight pertaining to nanostructure
growth. Here, we use scanning probe block copolymer lithography (SPBCL)
to create “nanoreactors” having attoliter volumes, which
confine Au NP nucleation and growth to features having diameters <150
nm on a substrate. With this technique, one can use in situ TEM to
directly observe and study NP coarsening and differentiate Ostwald
ripening from coalescence processes. Importantly, the number of metal
atoms that can engage in coarsening can be controlled with this technique,
and TEM “snapshots” of particle growth can be taken.
The size of the resulting nanostructures can be controlled in the
2–10 nm regime.