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Abstract The advancement of clean energy and environment depends strongly on the development of efficient catalysts in a wide range of heterogeneous catalytic reactions, which has benefited from transmission electron microscopic techniques in determining the atomic‐scale morphologies and structures. However, it is the morphology and structure under the catalytic reaction conditions that determine the performance of the catalyst, which has captured a surge of interest in developing and applying in situ/operando transmission electron microscopic techniques in heterogeneous catalysis. The major theme of this review is to highlight some of the most recent insights into heterogeneous catalysts under the relevant reaction conditions using in situ/operando transmission electron microscopic techniques. Rather than a comprehensive overview of the basic principles of in situ/operando techniques, this review focuses on the insights into the atomic‐scale/nanoscale details of various catalysts ranging from single‐component to multicomponent catalysts under heterogeneous catalytic, electrocatalytic, and photocatalytic reaction conditions involving both gas–solid and liquid–solid interfaces. This focus is coupled with discussions of the correlation of the atomic, molecular, and nanoscale morphology, composition, and structure with the catalytic properties under the reaction conditions, shining light on the challenges and opportunities in design of nanostructured catalysts for clean and sustainable energy applications.
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Review Article: Spectroscopic microreactors for heterogeneous catalysis
Microfluidic reactors with in situ spectroscopy have enabled many new directions of research over the last two decades. The miniature nature of these systems enables several key advantages in heterogeneous catalysis, which includes the reaction surface or interface accessible to spectroscopic equipment making the discovery of new catalytic materials possible. Devices fabricated with materials that are transparent to electromagnetic radiation enable in situ and in operando spectroscopy such as Raman, UV-Vis, and IR directly at the point of the reaction, and thus high fidelity, transient information on the reaction chemistry is available. Innovative designs with NMR, electrochemical impedance spectroscopy, x-ray techniques, or terahertz imaging have also advanced the field of heterogeneous catalysis. These methods have been successfully engineered to make major breakthroughs in the design of catalytic materials for important classes of chemical reactions. In this review, the authors provide an overview of recent advances in the design of microreactors with in situ spectroscopy for the study of heterogeneous catalysis to raise awareness among the vacuum science community on techniques, tools, existing challenges, and emerging trends and opportunities.
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- Award ID(s):
- 1701393
- PAR ID:
- 10584285
- Publisher / Repository:
- American Vacuum Society
- Date Published:
- Journal Name:
- Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films
- Volume:
- 37
- Issue:
- 5
- ISSN:
- 0734-2101
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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