Enhanced reactivity and selectivity of oxide-supported single atom catalysts: it is all in the local atomic environment!
- Date: Jul 2, 2024
- Time: 02:00 PM - 03:00 PM (Local Time Germany)
- Speaker: Prof. Talat S. Rahman
- UCF Trustee Chair Professor and Pegasus Professor, University of Central Florida, Department of Physics
- Location: Building M, Richard-Willstätter-Haus, Faradayweg 10, 14195 Berlin
- Room: Seminar Room
- Host: Interface Science Department
- Contact: nikolaus@fhi-berlin.mpg.de
Singly dispersed transition metal atoms on oxide surfaces, the so-called single atom catalyst (SAC) have recently been shown to attain chemical activity and selectivity for several technologically important reactions that surpass those of Pt single crystal surfaces, the prototype exemplary catalyst but with a large price tag. Apart from being cost-effective, single atom catalyst offer excellent opportunities for tuning their local environment and thereby their oxidation state, local coordination, and electronic structure. In this talk, I will present results of collaborative work with several experimental groups on transition metal atoms anchored on surfaces, with and without ligands, that have the potential to be cost-effective catalysts with high activity and product selectivity.
Examples will include Pd and Pt atoms anchored on ZnO that form a bimetallic local environment consisting of one Pd/Pt and three Zn atoms with high catalytic activity for generation of H2 through methanol partial oxidation (MPO) [1], larger than that of Pt-Zn nanoalloys. Then there is the case of Pt atoms stabilized in specific fine-tuned local coordination environments that exhibit strikingly distinct catalytic behaviors in reactions as varied as CO oxidation and NH3 oxidation, dependent on the calcination temperature [2]. I will also pay attention to the special role played by ligands (1,10-phenanthroline-5,6-dione (PDO)) in emergent catalytic properties of Pt single atoms stabilized on titania surfaces towards water gas shift reaction. I will draw attention to some factors that control the emerging functionalities of the above systems in controlled confinement.[1] Y. Tang, et al., Nano Lett. 20, 6255 (2020); T.B. Rawal, et al., ACS Catalysis 8, 5553-5569 (2018); T. Jiang et al., ACS Appl. Mater. Interfaces 16, 21757 (2024).[2] W. Tan, et al., Nat Commun. 13, 7070 (2022).