This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). This research award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports work by Professor Gerald Meyer at Johns Hopkins University to carry out fundamental/basic studies on molecular level events that occur at sensitized semiconductor interfaces. This work can one day lead to the efficient harvesting and storage of energy from the sun. The investigators utilize time resolved spectroscopic techniques to characterize excited states and electron transfer reactions that occur after metal-to-ligand charge-transfer (MLCT) excitation of transition metal compounds anchored to high surface area mesoporous nanocrystalline thin films comprised of the wide bandgap semiconductor anatase TiO2 or the insulator ZrO2. These studies are performed under excitation conditions where, on average, less than one excited state is created on each metal oxide nanocrystallite and under conditions representative of one sun or higher steady-state irradiances. The presence of multiple electrons in each nanocrystallite profoundly influences interfacial behavior even though the underlying principles are poorly understood. This research is directly related to a long-term goal of identifying materials that efficiently convert sunlight into useful forms of energy. If successful, an environmentally benign energy resource would be realized with an enormous economic and environmental impact. Scientifically a broad impact is assured as this proposal will train young scientists to be future professionals and forge links to interdisciplinary materials chemistry. Results from these fundamental studies are envisioned to one day enable the rational molecular-level design of integrated materials capable of harvesting sunlight, charge separation, and performing multi-electron transfer catalysis to form useful fuels.
