Speaker
Description
Activation of dioxygen attracts enormous attention due to its potential for utilization of methane and applications in other selective oxidation reactions. Employing periodic DFT calculations we discovered a cleavage of dioxygen over distant binuclear Fe(II).[1] Our experiments confirmed splitting dioxygen at room temperature and showed that pairs of the formed distant Alpha-oxygen species [i.e., (Fe(IV)═O)2+] exhibited unique oxidation properties reflected in an outstanding activity in the oxidation of methane to methanol at room temperature.[1] Designing a man-made system that mimicks the enzyme functionality in the dioxygen activation using both a different mechanism and structure of the active site represents a breakthrough in catalysis.[1]
Professor Yuriy Roman-Leshkov of MIT about our discovery:[2]
"Recently, Tabor et al. have observed the formation of Fe(IV)=O from O2 at room temperature by a pair of distant Fe(II) centers stabilized in the matrix of a zeolite. This delicately designed binuclear Fe(II) site converts methane into methanol at room temperature using O2 as oxidant, representing a breakthrough in methane oxidation catalysis."
"The direct methane-to-methanol conversion has been considered as one of the "holy grail" reactions in the field of catalysis."
The authors of the discovery were awarded the Czech science prize "Česká hlava Cena Invence“ in 2020.[3, 4]
In our contribution, we present the results of follow-up periodic DFT calculations used to investigate the effect of (i) the Al siting in the rings forming the cationic sites, (ii) the distance, (iii) the mutual geometrical position of the rings accommodating Fe(II), and (iv) the type of transition metal cation (Me(II) = Co(II), Mn(II), and Fe(II)) accommodated in the active centers on the activity of the distant binuclear Me(II) sites in splitting dioxygen. The outcome of our work reveals that employing periodic DFT and supercomputers we can suggest new materials which when experimentally prepared and tested have a high chance of being successful catalysts.[5-7]
References
(1) Tabor, E.; Dedecek, J.; Mlekodaj, K.; Sobalik, Z.; Andrikopoulos, P. C.; Sklenak, S. Dioxygen Dissociation over Man-Made System at Room Temperature to Form the Active Alpha-Oxygen for Methane Oxidation. Science Advances 2020, 6, eaaz9776.
(2) Yuan, S.; Li, Y. D.; Peng, J. Y.; Questell-Santiago, Y. M.; Akkiraju, K.; Giordano, L.; Zheng, D. J.; Bagi, S.; Roman-Leshkov, Y.; Shao-Horn, Y. Conversion of Methane into Liquid Fuels-Bridging Thermal Catalysis with Electrocatalysis. Advanced Energy Materials 2020, 10, 2002154.
(3) https://www.ceskahlava.cz/ceska-hlava/vitezove/tym-mgr-jiriho-dedecka-csc-dsc/ (accessed 04-25-2022).
(4) https://www.it4i.cz/o-it4i/infoservis/novinky/vyzkum-s-prispenim-superpocitacu-it4innovations-ziskal-cenu-ceska-hlava (accessed 04-25-2022).
(5) Dedecek, J.; Tabor, E.; Andrikopoulos, P. C.; Sklenak, S. Splitting Dioxygen over Distant Binuclear Transition Metal Cationic Sites in Zeolites. Effect of the Transition Metal Cation. International Journal of Quantum Chemistry 2021, 121, e26611.
(6) Mlekodaj, K.; Lemishka, M.; Sklenak, S.; Dedecek, J.; Tabor, E. Dioxygen Splitting at Room Temperature over Distant Binuclear Transition Metal Centers in Zeolites for Direct Oxidation of Methane to Methanol. Chemical Communications 2021, 57, 3472-3475.
(7) Tabor, E.; Lemishka, M.; Olszowka, J. E.; Mlekodaj, K.; Dedecek, J.; Andrikopoulos, P. C.; Sklenak, S. Splitting Dioxygen over Distant Binuclear Fe Sites in Zeolites. Effect of the Local Arrangement and Framework Topology. ACS Catalysis 2021, 11, 2340-2355.
