Speaker
Description
Atomically dispersed precious metals on oxide supports have recently become increasingly interesting catalytic materials.$^{1,2}$ Nonetheless, the non-trivial preparation and limited thermal and environmental stability of single atom catalysts (SACs) constitutes an issue for their potential applications. Here we show that an oxygen plasma pre-treatment of ceria surface serves to anchor Pt single atoms, making them resistant towards sintering and considerably more active in the CO oxidation reaction.$^{3}$ Through a combination of experimental results obtained on well-defined CeO$_{2}$(111) surfaces and theoretical calculations (performed by the Lopez’s group in Spain), we show that the O2 plasma causes surface nanostructuring and the formation of surface peroxo (O$_{2}$$^{2-}$) species, favoring the uniform and dense distribution of isolated strongly bonded Pt$^{2+}$ atoms. The beneficial effect of plasma-induced surface modification was demonstrated on powder Pt/CeO$_{2}$ SACs post-treated with oxygen plasma. We also examined effects of oxygen, hydrogen, and argon plasma on stability and reactivity of Pt SACs supported on MgO and Al$_{2}$O$_{3}$ in the propane dehydrogenation and acetylene hydrogenation reactions. The results obtained for different systems and reactions suggest that the plasma treatment can be used for stabilization of single atoms and also for tuning metal dispersion under reaction conditions, in turn affecting their catalytic performance.
References
1. J. Liu, ACS Catalysis 7, 34 (2017).
2. L. DeRita, et al., J Am. Chem. Soc. 139, 14150 (2017).
3. W. Wan, et al., Angew. Chem. Int. Ed. 61, e202112640 (2022).
| Abstract Number (department-wise) | ISC 20 |
|---|---|
| Department | ISC (Roldán) |
