2010.03.10

537, Engineering 5th Bld, Hongo Campus

Prof. Dionisios G. Vlachos
       Elizabeth Inez Kelley Professor of Chemical Engineering
       Director of Catalysis Center for Energy Innovation
       University of Delaware

Title: Complexity and emergent behavior in catalytic reactions: CO oxidation on gold and ammonia decomposition on single metals and bimetallics

Abstract: 

In this talk, complexity and emergent behavior of catalytic reactions will be presented with main focus on discovery of novel catalytic materials. In particular, the effects of support, and particle size and shape will be addressed. Two prototype reactions will be discussed: CO oxidation on Au supported on MgO and ammonia decomposition for hydrogen Production. Phenomenal structure sensitivity of ammonia is found experimentally by combining EXAFS, TEM, chemisorption, and reactivity data. In particular we show that not only size but also particle shape can affect activity dramatically. Multiscale modeling is in excellent agreement with data. We then formulate an optimization problem to predict best catalytic bimetallic materials that we subsequently design and demonstrate experimentally. We use multiscale modeling, combining density functional theory with kinetic Monte Carlo simulations, to understand the overall activity of CO on Au particles and small clusters. We find that oxygen Vacancies are critical in enabling charge transfer and thus molecular oxygen adsorption. Carbonate poisoning and catalyst restructuring are key processes in understanding activity of Au clusters.

Schedule: 15:00  ~ 17:00  Wednesday 10th March, 2010

Place: 537, Engineering 5th Bld, Hongo Campus

Attached file:  The 48th open seminar.pdf