(3at) Elucidating Reaction Mechanisms and Identifying Bottlenecks In Catalytic Processes

Kinetic and mechanistic investigations of chemical reactions can be clarified by deconstructing the series of elementary steps and individually interrogating their dependence on the prevalent reaction conditions and catalyst structure and composition.  The use of decidedly monofunctional systems is critical as an initial step, and consequently results are obtained on single crystal model systems of noble metals, bimetallics, and metal carbides as well as from noble metal clusters supported on inert supports.  Complexity can be incrementally restored by the inclusion of materials containing additional chemical functions. Utilizing transient and steady-state kinetic measurements in combination with in situ spectroscopy it is possible to identify "bottlenecks" in the reaction sequences which have consequences for absolute and relative turnover rates.  Selective decomposition and formation of heavy hydrocarbons and light oxygenates are investigated to ascertain the role of surface structure and composition as it pertains to stabilizing individual intermediates with the catalytic cycle.