Dr. Omar Abdelrahman

The chemical catalysis and reaction engineering lab led by Prof. Abdelrahman is focused on understanding and manipulating reaction interfaces existing at the intersection of fluid and catalyst phases. The research group leverages a wide array of experimental techniques to understand how external energetic stimuli alter reaction mechanisms, kinetics, and thermodynamics of both thermo and electro-chemical transformations proceeding on heterogeneous catalyst surfaces. As a leading member of the DOE Center for Programmable Energy Catalysis, Dr. Abdelrahman has led the effort to develop the concept of programmable catalysis, where energetic oscillations of a catalytic material accelerate the turnover rate at which chemical transformations proceed. Research in the group additionally focuses on the reaction environment surrounding catalytic surfaces, with an emphasis on understanding and controlling non-ideal thermodynamic environments relevant to renewable chemical transformations. The group is also committed to advancing accessible and affordable science by developing and disseminating experimental designs that lower the barrier to entry in catalysis research.

DYNAMIC ELECTROCATALYSIS

Dynamic electrocatalysis, the delivery of applied potential oscillations to an electrochemical electrode at precisely controlled frequencies, greatly enhances electrocatalytic activity and selectivity relative to static counterparts. Acceleration of the catalytic cycle through this dynamic approach is maximized at a unique range of frequencies, proposed to be in resonance with the kinetic timescales of individual surface reactions.  Through microkinetic modeling, computational calculations, and experimental kinetics, we are developing and researching the ability to accelerate the activity of existing materials through periodic energetic oscillations applied directly to the catalytic surface.

PROGRAMMABLE CATALYSIS

Merging the area of heterogeneous catalysis and microelectronics, we are controlling the electronics of metal atoms in real time to create active sites that experience continuous energetic fluctuations. The real time and in situ control of metal active site electronics allows for the programmable modulation of thermocatalytic activity.

CONFLUENCE OF CATALYTIC KINETICS AND THERMODYNAMICS

The reaction microenvironment surrounding a catalytically active site provides a rich dial through which to tune catalytic activity and selectivity for all chemical transformations. By combining surface sensitive techniques relevant to understanding chemical kinetics and thermodynamics on catalytic surfaces, we are interested in understanding the confluence of the two energetic domains, and how they can be manipulated to afford enhanced catalytic performance.

ADSORPTION THERMODYNAMICS

Understanding the energetics associated with adsorption phenomena on solid surfaces is core to the design of heterogeneous catalysts. While enthalpic contributions are relatively well understood, the mobility of adsorbates on the surface as captured through entropy is far more elusive. We develop experimental techniques that allow us to more directly measure adsorbate entropy and mobility in the porous networks of high surface area solids critical to catalytic technologies.