Interactions between Oxygen Atoms on Pt(100): Implications for Ordering during Chemisorption and Catalysis

Abstract

We present a DFT analysis of the interactions between chemisorbed oxygen on the unreconstructed (1x1)-Pt(100) surface. These interactions control ordering of O not just for single-species adsorption, but also within O domains during coadsorption and reaction with other species such as CO. The calculations indicate that O prefers bridge sites, as deduced previously. In addition, we find a large difference in the interactions between O at different types of bridge site pairs separated by one lattice constant. There is strong repulsion for pairs separated by a Pt atom, but only a weak interaction for pairs separated by a fourfold hollow site. This finding elucidates the tendency for striped (nx1)-O ordering often observed in chemisorption and reaction studies.

Biomass hydrodeoxygenation catalysts innovation from atomistic activity predictors

“…The hollow sites are the lowest energy adsorption sites for oxygen on most of the fcc(100) surfaces as reported in previous publications [125,127,[140][141][142]. Only for Ir and Pt were the bridge sites found to be more stable which is in agreement with other theoretical calculations [143][144][145][146][147]. On the bcc(100) surfaces, the adsorption of oxygen occurs preferentially on the hollow sites of Fe(100) and on the bridge sites of Mo(100) and W(100).…”

Kinetic Monte Carlo Simulation of Statistical Mechanical Models and Coarse-Grained Mesoscale Descriptions of Catalytic Reaction–Diffusion Processes: 1D Nanoporous and 2D Surface Systems

“…Also there is an attraction between NN pairs of O on vicinal br sites (but a repulsions of NN germinal br sites). 290 Thus, a natural adsorption rule has O 2 dissociate directly onto a pair of empty NN vicinal br sites and to remain on those sites. 179 However, for adsorption onto pure Oadlayers, we prescribe that adsorption is blocked if any of the six br sites a distance d = a/√2 is occupied or one of the four geminal br sites a distance d = a from these.…”

Multiscale Approach to the Dissociative Adsorption of Oxygen on a Highly Dispersed Platinum Supported on γ-Al2O3

“…Systematic DFT calculations for clusters of variable size show that size effect is substantial for the adsorption of oxygen below about 150 atoms . Although many DFT studies deal with the adsorption of oxygen on flat or corrugated platinum surfaces, ,,,,− studies taking into account the support effect on the interaction of oxygen with platinum clusters are much scarcer, and generally concern very small clusters or single atoms and a single O 2 molecule. ,, A systematic investigation of the interaction of oxygen with sub-nanometric platinum cluster, typically Pt 13 , supported on γ-Al 2 O 3 , taking into account the effect of O coverage, function of the temperature and O 2 partial pressure, and possible reconstructions, is thus needed. The approach previously undertaken in the case of hydrogen interaction with Pt 13 /γ-Al 2 O 3 , revealing strong reconstructions of the metallic phase and modulation of the metal–support interaction upon variation of the H coverage, , is worth being extended to oxygen.…”