(520b) Metal Core/Surface Oxide Shell Catalysts for C-O Bond Activation
Herein, we use a combination of the state-of-the-art density functional theory, ab initio molecular dynamics coupled with simulated annealing, and microkinetic modeling to elucidate the structure and properties of the NC catalytic site. In addition, we develop a geometric model that allows comparison of first principlesâ?? structure predictions with in situ EXAFS/XANES measurements and ex situ XRD data. A bimetallic alloy core/surface oxide shell structure with Co segregated to the surface is found to be consistent with the experimental data. We identify the strong interaction between the CoxOy surface oxide and the underneath metal to be crucial for the kinetic stability of the oxide in a highly reducing environment. Finally, we elucidate the â??reverse Mars van Krevelenâ? mechanism of hydrogenolysis.
1.Â Luo, Yun, Mironenko, Goulas, et al. Mechanisms for High Selectivity in Hydrodeoxygenation of 5-Hydroxymethylfurfural over PtCo Nanocrystals. Under Review.