About the Seminar:
The very diverse geometrical and electronic structures of inorganic clusters, and in particular early-transition metal polyoxometalates (POMs), give these complex polyanions an extensive, usually reversible and tunable redox chemistry and other properties of value in several fields. A subset of this chemistry is that POMs are effective catalysts for oxidations, including air(O2)-based oxidations, several of which have been commercialized, and water oxidation catalysts (WOCs) in conjunction with solar fuel production. The energetics, hydrolytic chemistry and multi-electron-transfer chemistry of POM WOCs will be discussed, and some conclusions of studies in this area after our intial papers (2008 Angew. Chem. Int. Ed., and 2010, Science) will be described.
The second effort, which is quite new, but intriguing, novel and promising based on diverse biological studies, involves the development of a “catalytic anticancer agent”. These POMs gets into tumor cells and once inside catalyze the air(O2)-based oxidation of the protective antioxidants (primarily glutathione) within the tumor cells resulting in a redox potential imbalance and death of the tumor cells. The selectivities are very high for a range of tumor cells versus healthy cells and we have documented actual catalytic reactions inside living cells. The talk will finish with a look at some fundmental studies of ionic strength and ion pairing properties of POMs. These properties, like redox potential, impact nearly all other attributes and applications of POMs.
About the Speaker:
Dr. Craig L. Hill, the Goodrich C. White Professor at Emory University, has been studying catalysis, reaction mechanisms and materials science for 40 years. Most of his current research focuses on solar fuels, oxidation, decontamination, and multi-electron transfer processes, frequently with an emphasis on nano-scale materials and POM derivatives. His research involves extensive structural characterization (X-ray crystallography, NMR, etc.), many spectroscopic and electrochemical techniques in addition to kinetics and most recently in operando synchrotron studies with Brookhaven National Lab (BNL) and Argonne National Lab (ANL) collaborators. Dr. Hill has trained about 140 graduate students and postdoctoral research associates. Google Scholar lists over 600 publications with ~410 publications in peer-reviewed journals that have been cited ~28,000 times (H index = 88). Four of these have already exceeded 1000 citations. He has been the recipient of three ACS awards and many others and is a Fellow of AAAS, the Victorian Institute of Chemical Sciences (VICS), the Academia Europaea (AE) and the Royal Society of Chemistry (RSC).