LAC L. M. Venanzi Lecture 2016
- D-CHAB
- LAC
The LAC is proud to welcome Prof. Dr. T. Don Tilley (UC Berkeley) as the lecturer during the LAC L. M. Venanzi Distinguished Lecture 2016. He will deliver two talks on April 12 and April 13.
1st talk, Tuesday, April 12, 2016, 17.15, HCI J7
The Role of High Oxidation State Metal Species in Water
Oxidation and Solar Fuels Production
The integration of photovoltaics and catalysts into a useful system for solar energy conversion will require a number of advances, such as the development of high efficiency, nanoscaled photovoltaic units, the discovery of inexpensive electrocatalysts for the half-reactions of interest, and the incorporation of efficient catalysts onto the surfaces of the photovoltaics. For schemes based on water oxidation, it is possible to envision catalysts derived from molecular transition metal complexes, or from inorganic solid-state materials. Molecular catalysts for water oxidation are somewhat controversial, since ligands in the catalytic species may readily undergo degradation under highly oxidizing conditions. Also, it is difficult to confidently associate catalytic activity with a particular molecular species, since these may oxidatively decompose to catalytic metal oxide materials under the conditions of electro- or photo-catalysis. However, molecularly derived catalysts offer a number of potential advantages, including the synthetic tunability of structure-activity relationships and chemical properties. Also, molecular precursor methods may be used to produce nanostructured, robust heterogeneous catalysts of controlled structure. The study of model, high-valent molecular species can provide key insights into the mechanism of water oxidation, and thereby help bridge the gap between heterogeneous and homogeneous systems to allow for more rational design of catalysts. This presentation will describe high-valent metal complexes and clusters, and a detailed mechanism for the evolution of oxygen via water oxidation at a tetra-cobalt cubane complex.
followed by a get-together in front of J7
Guests are most welcome
2nd talk, Wednesday, April 13, 2016, 17.15, HCI J7
The Role of High Oxidation State Metal Species in Water
Oxidation and Solar Fuels Production
Organosilicon compounds play an important role as reagents and intermediates in organic synthesis, and as monomers for the production of oligomers, polymers and composites used in various applications. Thus, new catalytic transformations are highly desired, and there is considerable interest in development of more cost-effective and selective hydrosilylation catalysts. A general approach to addressing these issues involves discovery of new fundamental reaction steps for activations of appropriate substrates. This presentation will describe new types of metal-silicon complexes that enable mechanisms for transformations of organosilanes, including hydrosilylation. Such complexes include unsaturated metal silylene complexes, sigmacomplexes of cationic metal centers, and coordinatively unsaturated, first-row transition metal complexes.
The chemistry of two-coordinate, open-shell metal complexes has not been extensively explored. Such research may reveal new transformations for chemistry and catalysis that utilizes earth-abundant metals. The latter activity involves incorporation of a first-row metal into a ligand environment that allows it to follow catalytic pathways analogous to those currently associated with complexes of heavier metals. For example, a redox-active ligand might allow a metal complex to engage in two-electron substrate activations (oxidative additions), rather than the one-electron redox change that the metal would naturally prefer. Other strategies for utilization of first-row metals in catalysis might leverage new mechanisms that feature intermediates and transition states peculiar to the metals of interest. This consideration might leverage a unique property of first row transition metals, in their ability to support reactive complexes with exceedingly low coordination numbers. This presentation will describe synthetic, structural, mechanistic and reactivity studies that reveal new opportunities in catalysis via discovery of fundamental transformations at a first-row transition metal center.
followed by a get-together in front of J7
Guests are most welcome LAC