Seminar | September 29 | 4-5 p.m. | 120 Latimer Hall
The interconversion of electrical and chemical energy requires the coupling of electron transfer with substrate bond rearrangement. This can be achieved via inner-sphere electron transfer at the surface exposed active sites of metallic heterogeneous electrocatalysts or via outer-sphere redox mediation facilitated by a homogeneous molecular electrocatalysts. Molecular electrocatalysts yield readily to synthetic alternative of their redox properties and secondary coordination sphere, permitting systematic tuning of catalyst activity and selectivity. Similar control is difficult to achieve with heterogeneous electrocatalysts because they typically exhibit a distribution of active site geometries and local electronic structures, which are recalcitrant to molecular-level synthetic modification. However, metallic heterogeneous electrocatalysts benefit from a continuum of electronic states which distribute the redox burden of a multi-electron transformation, enabling more efficient catalysis. We have developed a simple synthetic strategy for conjugating well-defined molecular catalyst active sites with the extended states of graphitic solids. These graphite-conjugated catalysts activate substrates via inner-sphere electron transfer pathways typical of metal surfaces while retaining their molecular fidelity and synthetic tunability. Our latest efforts to develop this new class of catalysts will be discussed.
Light refreshments will be served at 3:50 at The Coffee Lab