Special Seminar - Department of Chemistry
Prof. Anatoly Frenkel
Physics Department, Yeshiva University
Synchrotron Catalysis Consortium at Brookhaven National Laboratory
Understanding mechanisms of work in nanoscale systems (catalysts, sorbents, actuators, sensors…) is often hindered by their inherent complexity and by our inability to identify and characterize their elusive “active” sites. In the size range of 1-5nm, they feature a variety of structural motifs, sizes, shapes, compositions, degrees of crystalline order as well as multiple temporal scales. An additional challenge is that only a fraction of them are actors in the catalytic performance, while majority are merely spectators, and play no direct role, but are still accounted for in any experiment. Significant progress in developing modern characterization toolbox for studying functional nanomaterials can be achieved only when active species can be reliably isolated from spectators, and their role in mechanism of work is understood. In our approach the activity of nanomaterial is measured at the same time with other characteristics, obtained by advanced scattering, spectroscopy and imaging methods. Correlating multiple techniques allows us to identify active species with high spatial, temporal and energy resolutions. Examples will be drawn from our work with homogeneous and heterogeneous catalysts, electromechanical materials and other systems of broad interest.
