Hosted by: Qin Wu

Center for Functional Nanomaterials Seminar Cu-CHA in Emission Control Dr. Xiaofan Yang BASF Corporation Friday, July 10, 2015 11:00 a.m. Building, 735, Conference Room A Chabazite supported Cu is the most promising catalyst platform for implementing a NH3/urea-based Selective Catalytic Reduction (SCR) system to remove hazardous NOx gases from the lean-burn engine exhaust. Whereas in-depth spectroscopic and other studies have attempted to identify key features of the catalytic cycle previously, a deep understanding of the SCR mechanism amenable for a systematic improvement of the catalyst performance continues to be elusive. To establish a more rational approach to catalyst optimization and identify chemically sound design principles based on the thermodynamics and kinetics of the key steps of the underlying NOx-transformations we developed a quantum chemical model and benchmarked it to match vibrational data from Diffuse Reflectance Infrared Fourier Transform spectroscopy resulting in plausible assignments of each observable intermediate to specific oxidation states of Cu and NO-binding properties. This approach allows for making a much more precise assignment of the experimental vibrational data to key intermediates potentially involved in the catalytic cycle of the SCR reaction and provides a high-resolution model that can be examined to develop a micromechanistic proposal for the catalytic reaction cycle that is chemically meaningful and is logically consistent. In addition, the presentation also covers industrial application utilizing Cu-CHA in emission control. Host: Qin Wu