“Heterogeneous Catalysis for Energy Efficiency: The Roles of Dynamic Defects”
Dr. Cynthia Friend, Harvard University
Heterogeneous catalysis is a key technology for conversion of chemicals and synthesis of many materials. Gold-based materials have recently been used for selective and low-temperature “green” processes. We have investigated oxidative transformation of alcohols on metallic Au under model conditions at low pressure and also at atmospheric pressure during a catalytic reaction. We have also investigated transformation of organic oxygenates on titania and found that interstitial defects play a key role in stabilizing intermediates and in inducing reactions. A combination of atomic-scale imaging and spectroscopy is used to establish reaction mechanism and to demonstrate the key role of dynamic defects in promoting heterogeneous reactions.
Cynthia Friend received her PhD in chemistry from the University of California, Berkeley, in 1981. She is now the Theodore Williams Richards Professor of Chemistry and a professor of materials science at Harvard, where her group focuses on important catalytic reactions and on making new materials with key chemical functionality. The major themes in her group’s research are:
1) The development of a mechanistic framework for selective catalytic syntheses promoted by oxygen on coinage metals (Au, Ag and Cu) and their alloys, with the objective of providing a basis for designing green chemical processes.
2) Investigation of hybrid metal/metal oxide materials, including nanostructures, for chemical and photocatalysis. One aspect of this work is driving thermodynamically uphill reactions, such as CO2 reduction and water splitting.
3) The study of new methods for controlled doping of semiconductor materials so as to modify their optical properties using femtosecond lasers and novel methods for introducing dopant precursors. The objective is to create materials that efficiently harvest solar energy for photovoltaics and photoelectrochemistry.