A vial of nanocrystals in solution, which serve as
“electronic glue” for semiconductor-based technologies.
of Chicago Postdoctoral Scholar Maksym Kovalenko
(left) working with nanocrystals in a glovebox in the laboratory of Dmitri
Talapin, assistant professor in Chemistry. Working in the environmentally
controlled conditions of the glovebox permits researchers to perform chemical
procedures not possible under room conditions.
Photos by Dan Dry.
Researchers at the University of Chicago
and Lawrence Berkeley National Laboratory have developed an “electronic glue”
that could accelerate advances in semiconductor-based technologies, including
solar cells and thermoelectric devices that convert sunlight and waste heat,
respectively, into useful electrical energy.
Semiconductors have served as choice materials for many electronic and optical
devices because of their physical properties. Commercial solar cells, computer
chips and other semiconductor technologies typically use large semiconductor
crystals, but these are expensive and can make large-scale applications such as
rooftop solar-energy collectors prohibitive.
Dmitri Talapin is an assistant professor in Chemistry at the
University of Chicago.
As an alternative, engineers see great potential in
semiconductor nanocrystals that sometimes measure just a few hundred atoms
each. Nanocrystals can be readily mass-produced and used for device
manufacturing via inkjet printing and other solution-based processes. But a problem
remains: The crystals are unable to efficiently transfer their electric charges
to one another due to surface ligands - bulky, insulating organic molecules
that cap nanocrystals.
The “electronic glue” developed in Dmitri Talapin’s laboratory at the University of Chicago solves the ligand problem. The
team describes in the journal Science
how substituting the
insulating organic molecules with novel inorganic molecules dramatically
increases the electronic coupling between nanocrystals. The University of Chicago
licensed the underlying technology for thermoelectric applications to Evident Technologies
: “Colloidal Nanocrystals with Molecular Metal
Chalcogenide Surface Ligands,” Maksym V. Kovalendo, Department of Chemistry,
University of Chicago; Marcus Scheele, Molecular Foundry, Lawrence Berkeley
National Laboratory; and Dmitri V. Talapin, Department of Chemistry, University
of Chicago, and Center for Nanoscale Materials, Argonne National Laboratory, Science
June 12, 2009.
: American Chemical Society Petroleum Research Fund, The Chicago
Energy Initiative, U.S. Department of Energy and Evident Technologies Inc.