Neurock

As first noted by Neurock etal. [24], the Pt(lOO) surface provides sites for extremely low barriers of NO and N2 recombination. For NO, the energetics on... 

Neurock and coworkers [M. Neurock, V. Pallassana and R.A. van Santen, J. Am. Chem. Soc. 122 (2000) 1150] performed density functional calculations for this reaction scheme up to the formation of the ethyl fragment, for a palladium(lll) surface. Figure 6.38(a) shows the potential energy diagram, starting from point at which H atoms are already at the surface. As the diagram shows, ethylene adsorbs in the Jt-bonded mode with a heat adsorption of 30 kj mol and conversion of the latter into the di-a bonded mode stabilizes the molecule by a further 32 kJ mol . ... 

Figure 6.39. Structure of the transition states for ethylene hydrogenation, corresponding to Fig. 6.38 see text for details. [Adapted from M. Neurock, V. Pallassana and R.A. van Santen.J. Am. Chem. Soc. 122 (2000) 1150.]...

Boscoboinik, J.A., Plaisance, C., Neurock, M. and Tysoe, W.T. (2008) Monte Carlo and density functional theory analysis of the distribution of gold and palladium atoms on Au/P(lll) alloys. Physical Review B - Condensed Matter, 77, 045422-1-045422-6. 

Ab initio methods allow the nature of active sites to be elucidated and the influence of supports or solvents on the catalytic kinetics to be predicted. Neurock and coworkers have successfully coupled theory with atomic-scale simulations and have tracked the molecular transformations that occur over different surfaces to assess their catalytic activity and selectivity [95-98]. Relevant examples are the Pt-catalyzed NO decomposition and methanol oxidation. In case of NO decomposition, density functional theory calculations and kinetic Monte Carlo simulations substantially helped to optimize the composition of the nanocatalyst by alloying Pt with Au and creating a specific structure of the PtgAu7 particles. In catalytic methanol decomposition the elementary pathways were identified... 

Desai SK, Neurock M. 2003. First-principles study of the role of solvent in the dissociation of water over a Pt-Ru alloy. Phys Rev B 68 075420. 

The advantages of the simple approach outlined above are the limited number of water molecules needed in the simulation and the well-defined water structure. The major drawback is that, owing to the periodicity, this water structure fits best on a (111) or (lll)-like surface, e.g., (211). There are at least two other approximations to model the water interaction. One is to include a large number of water molecules and apply molecular dynamics to determine a structure for the water and include this water arrangement in the simulations [Filhol and Neurock, 2006]. The drawbacks of this approach are the computational time required and the results sensitivity to the water structure. 

FiUiol JS, Neurock M. 2006. Elucidation of the electrochemical activation of water over Pd by first principles. Angew Chem Int Ed 45 402-406. 

Kieken LD, Neurock M, Mei DH. 2005. Screening by kinetic Monte Carlo simulation of Pt-Au(lOO) surfaces for the steady-state decomposition of nitric oxide in excess dioxygen. J Phys Chem B 109 2234-2244. 

Rossmeisl J, Norskov JK, Taylor CD, Janik MJ, Neurock M. 2006. Calculated phase diagrams for the electrochemical oxidation and reduction of water over Pt(l 11). J Phys Chem B 110 21833-21839. 

Accordingly, Neurock and co-workers have developed models for the electrochemical interface that retain this concept of hexagonal stmcture over close-packed metal surfaces [FiUiol and Neurock, 2006 Taylor et al., 2006c]. With the use of a screening charge as described in Section 4.3, the sensitivity of the stmctural parameters of water with respect to the electrochemical environment were explored [Taylor et al., 2006a]. The predominant effect stems from the polar nature of the water molecule, in which the water molecules are observed to rotate as a function of the applied potential. 

Figure 4.13 The transition state for CO + OH coupling to form COOH on the Pt(lll) surface. The transition state is stabilized in the aqueous model system through hydrogen bonding between the hydroxyl species and a nearby water molecule [Janik and Neurock, 2006].

Cao D, Lu G-Q, Wieckowski A, Wasileski SA, Neurock M. 2005. Mechanisms of methanol decomposition on platinum A combined experimental and an initio approach. J Phys ChemB 109 11622-11633. 

Desai S, Neurock M. 2003a. A first principles analysis of CO oxidation over Pt and Pl66.7%Ru33.3% (111) surfaces. Electrochim Acta 48 3759-3773. 

Desai SK, Neurock M, Kourtakis K. 2002. A periodic density functional theory study of the dehydrogenation of methanol over Pt(lll). J Phys Chem B 106 2559-2568. 

Janik MJ, Neurock M. 2006. A first principles analysis of the electro-oxidation of CO over Pt(lll). Electrochim Acta 52 5517-5528. 

Janik MJ, Taylor CD, Neurock M. 2007. First principles analysis of the electrocatal3ftic oxidation of methanol and carbon monoxide. Top Catal 46 306-319. 

Taylor CD, Neurock M. 2005. Theoretical insights into the structure and reactivity of the aqueous/metal interface. Curr Opin Solid State Mater Sci 9 49-65. 

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