Research Projects

Nanocrystal synthesis

In the size range 1-10 nm, the mesoscale domain, the electronic structure and surface topography of nanocrystals changes dramatically.  Careful control of particle morphology at the mesoscale is a significant objective in nanocrystal synthesis. 

Our efforts will focus on methods for the synthesis of well defined nanocrystals and polydomain nanocrystals.  We have developed a nonhydrolytic synthesis of ruthenium nanocrystals that led to isotropic nanocrystals and polycrystalline branched particles (Figure 1).

Figure 1.  High resolution electron micrographs of ruthenium nanocrystals.  Left: isotropic Ru nanocrystal viewed through the 0001 axis; middle:  isotropic Ru nanocrystals (circled nanocrystal is in the left image); right:  polycrystalline branching Ru nanoparticle.

A long term goal in our laboratory is to develop polydomain nanostructured materials that can capture the energy from photons and catalyze endothermic electron transfer reactions.  Semiconductor nanocrystals decorated with functional components, such as molecular dyes or catalyst particles, are candidate materials that can host the multiple processes required for photocatalysis (photon absorption, exciton generation, separation of charge, and redox catalysis).  Ultimately, artificial photosynthesis as an application of this research, could lead to solar energy utilization on large scales.

Organometallic main group chemistry

Some foci of main group organometallic chemistry include the exploration of new types of bonding (multiple metal-metal bonds, partial bonds), stabilization of unusual oxidation states, molecular recognition, and synthesis of exceptionally powerful Lewis acids.  Given that the properties and reactivity of a molecule are dependent on its composition and shape, it is desirable to have the ability to conveniently synthesize a molecule soon after its conception in the imagination (whether borne out of curiosity, fundamental interest, or with a practical aim in mind).  A large synthesis toolkit should be available.

An example of a recently developed synthetic method is the reaction of an aryldistannane with indium(III)chloride, which leads to exchange of the main group metals, and formation of an aryldiindium compound in high yield (scheme 1).

Scheme 1.  Indium-Tin exchange at an aryl position as a route to aryl-indium compounds.