13 research outputs found
Theoretical Investigation of the Mechanism of the WaterâGas Shift Reaction on Cobalt@Gold CoreâShell Nanocluster
We
studied the mechanism of the waterâgas shift reaction
(WGSR; CO + H<sub>2</sub>O â CO<sub>2</sub> + H<sub>2</sub>) catalyzed by Co<sub>6</sub>@Au<sub>32</sub> coreâshell nanoalloy
using density-functional theory (DFT) calculations to investigate
the bimetallic effects on the catalytic activation. The molecular
structures and adsorbate/substrate interaction energies were predicted,
along with the potential energy surface constructed using the nudged
elastic band (NEB) method. Our results indicated that the energetic
barriers of the two hydrogen dissociation reactions are lower on the
coreâshell nanoalloy than on Au<sub>38</sub>. Furthermore,
all of the related chemical species of the WGSR can adsorb stably
on Co<sub>6</sub>@Au<sub>32</sub> to allow the reactions to take place
under ambient pressure. To gain insight into the synergistic effect
in the catalytic activity of the Co<sub>6</sub>@Au<sub>32</sub> nanoalloy,
the nature of the interaction between the adsorbate and substrate
was analyzed by detailed electronic local densities of states (LDOS)
as well as molecular structures