Project description
Single-atom catalysis is gaining the lead in a crowded field
Catalysts are essential to rapid production of specific chemicals in high quantity, speeding reaction rates without being consumed by the reactions themselves. However, despite not being consumed, they are typically precious metals – catalysis research is driven in large part by the need to reduce the utilisation of these materials. Single-atom catalysts (SACs) consisting of single atoms dispersed on a support are at the forefront of heterogeneous catalysis research, reducing the need for precious metals and potentially ‘greening’ chemical production for a wealth of applications. However, lack of understanding of structure-function relationships has impeded rational design. The EU-funded E-SAC project is characterising robustly anchored metal atoms on five industrially relevant supports and evaluating their activities to identify the best performers for specific reaction types. It will open a new era of rational design of SACs for a greener and more sustainable chemical industry.
Objective
Rare and expensive metals tend to be the best catalysts, and minimising or replacing them is a major research target as we strive to develop an economy based on more environmentally-friendly, energy-efficient technologies. “Single-atom” catalysis (SAC) represents the ultimate in efficiency, and the chemical bonds formed between the metal atom and the support mean these systems strongly resemble the organometallic complexes utilized in homogeneous catalysis. If all active sites were identical, single-atom catalysts (SACs) could achieve similar levels of selectivity, and even be used to “heterogenize” difficult reactions that must be currently performed in solution. There is a problem however: homogeneous catalysts are designed based on well-understood structure-function relationships. In SAC, the structure of the active site is unknown, thus rational design is impossible.
My group in Vienna has pioneered the use of the model supports to understand fundamental mechanisms in SAC. Our work with Fe3O4(001) proves that we can precisely determine and even selectively modify the active site, and unravel the role of structure in catalytic activity. Real progress, however, requires realistic active sites, realistic supports, and realistic environments. In this project, I describe how we will determine the sites that robustly anchor metal atoms on five of the most important supports in ultrahigh vacuum (UHV), and test their performance in newly-developed high-pressure and electrochemical cells. The origins of selectivity for PROX, hydrogenation, hydroformylation, methane conversion, and the oxygen reduction reaction (ORR) will be elucidated, and the best atom/support combinations for each reaction identified. Robust XANES and IRAS spectra will allow us to bridge the complexity gap and recreate the optimal active sites on real SACs and lead the way into a new era in which heterogeneous catalysts are designed for purpose, based on a fundamental understanding of how they work.
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Programme(s)
Funding Scheme
ERC-COG - Consolidator GrantHost institution
1040 Wien
Austria