Purdue Researchers Create a Paradigm Shift in Catalyst Active Site Categorization, Opening Doors to New Catalyst Design
In collaboration with researchers in the United States, China, and the Netherlands, Davidson School of Chemical Engineering’s Dr. Zhenhua Zeng and Professor Jeffrey Greeley, have advanced catalysis research and catalyst design through their exploration of active sites. Their findings not only offer valuable perspectives on prior catalytic reactivity and active site studies but also forecast the development of new catalysts with notably enhanced performance.
The usage of heterogeneous catalysts in chemical reactions is widespread, with the understanding that high catalytic activity occurs only on specific surface sites. "Determination of the molecular structure of catalytic active sites is a central and longstanding goal of catalysis science. Current research identifies and classifies these active sites through distinct surface motifs, such as steps and terraces. This categorization often oversimplifies the complexity of active site identification, which can lead to uncertain classification of active sites and incorrect predictions of catalytic activity. Thus, this misidentification hinders opportunities for catalyst design," stated Professor Greeley.
Published in Nature, Site-specific reactivity of stepped Pt surfaces driven by stress release, reveals a solution for the oversimplified categorization: atomic site-specific reactivity driven by surface stress release, which was often overlooked in the current classification process.
The findings generated by this research allow for a new lens through which researchers view catalytically active atomic sites and the principles governing the design of heterogeneous catalysts.
Collaborator, Professor Marc Koper of Leiden University stated, “This work is a beautiful example of how a dedicated collaboration between high-quality computations and experiments can bring unique insight into a long-standing issue in surface electrocatalysis, namely how and if local surface strain can influence chemical reactivity. I am delighted to have been part of this collaborative effort.”
Additional collaborators of this work include researchers affiliated with Hunan University, Leiden University, and Clarkson University.
d-Band Center Shift
Figure (Above): No two sites are alike in local strain, electronic structure (d-band center) and surface reactivity. For example, for the d-band center, the overall shape is like a two-tower suspension bridge. One tower is on the upper step, and another tower is on the lower step. Maxima of atomic site-specific strain and d band center shift are located around both sides of the step edges. Minima are located away from the step edges.
Read the full Nature paper
Written by: Margaret Padgett, padget12@purdue.edu