David Waldeck Department Chair of Chemistry
Research
Nanoscale manipulation of electrons and photons
Keywords: Nanophotonics, Charge transfer, Molecular conductance, Semiconductor
Nanoparticles, Luminescence.
Professor Waldeck's research program uses methods of spectroscopy, electrochemistry, and microscopy to investigate primary processes in the condensed phase, which includes liquids, solids and liquid/solid interfaces. Current themes of his research are the fundamental understanding of electron transfer reactions, electron transport in supramolecular structures, and nanophotonics.
Solution Studies
His research program studies electron transfer processes experimentally in order to directly evaluate and improve theoretical models. His studies focus on the influence of solvents on the reaction rate, via solvation, friction, and electronic coupling. Some recent work has shown how to use molecular solvation models to describe the energetics of electron transfer reactions in solvents ranging from non-polar to highly polar, demonstrated how solvent dynamics can sometimes control electron transfer rates, and observed the transition of an electron transfer mechanism from the nonadiabatic to the strong coupling limit. The current research efforts are aimed at understanding the nature of charge tunneling in aqueous media and the importance of fluctuations on electron transfer.
Interfacial Charge Transfer
This effort probes charge transfer through monolayers and individual molecules by electrochemical and/or conducting probe methods. Previous work has used electrochemical studies to elucidate how the molecular properties (e.g., electronic character, chirality, and the nature of the molecule-electrode linkage) affect the observed tunneling barriers and molecular conductivities. Current work is investigating how to manipulate the electronic and chemical nature of monolayer films to enhance the electronic interaction between a redox moiety and the electrode, with a particular focus on better understanding how to ‘wire’ biomolecules (proteins and oligonucleotides) to electrodes.
Nanophotonics
Technological breakthroughs in fabrication and characterization are allowing his group to probe the nature of light-matter interactions (photonics) for nanostructures and molecular assemblies. This work aims to develop a better understanding of the novel optical properties displayed by nanostructures and how to exploit them for applications in sensing and energy conversion.
