The Adsorption and Dissociation of O₂ on Cu Low-Index Surfaces

Abstract

The extended LEPS of O(2)-Cu single crystal plane systems is constructed by means of 5-MP (the 5-parameter Morse potential). Both the adsorption and dissociation of O(2) on Cu low-index surfaces are investigated with extended LEPS in detail. All critical characteristics of the system that we obtain, such as adsorption geometry, binding energy, eigenvalues for vibration, etc., are in good agreement with the experimental results. Our calculated results suggest there are many differences between O(2)-Cu (110) and O(2)-Pd (110) systems. On a Cu (110) surface, O(2) adsorbs in a tilted configuration and there are two lowest energy dissociation channels along the [001] and [10] directions, respectively. We speculate that the adsorption geometry of O(2) on the metal surfaces relates to the lattice constant of metal. Meanwhile, We use the concepts of the molecular dissociation limit and the surface dissociation distance to analyze again the dissociation mechanism of the O(2) on the low-index surfaces.

Adsorption of carbon monoxide on Pd (210) and (510) surfaces

“…The extended LEPS constructed by 5‐MP is a credible potential function based on the experimental information of the interaction between CO and Pd. We have successfully studied the system of O‐Pd, stepped systems of O‐Pd (311) and molecular adsorption systems of O 2 ‐Cu, CO‐Ni, O 2 ‐Pd, and obtained results that agreed well with the experimental data.…”

“…In this paper, we construct the extended LEPS by three pair‐potential functions as such: one is a Morse function employed for the gaseous diatom and the 5‐MP is used for the other two. 5‐MP has been explicated in the literature . Here, stating briefly as follows: on the assumption that the metal cluster is frozen, the interaction energy as the 5‐MP between an atom (which coordinate is specified by ) and the whole metal surface cluster can be written in the form of a Morse potential: …”

“…In Eqn , there are five adjustable parameters: D , β , R , Q 1 and Q 2 have been described in detail in the literature . The five adjustable parameters of the C–Pd and O–Pd are obtained and listed in Table .…”

Dissociative Adsorption of Oxygen on Clean Cu(001) Surface

“…This agrees with the result by the cluster calculation 9 that the reaction path over the hollow site is the most favorable with little dissociation barrier to these sites on the Cu(001) surface. Later, more detailed cluster calculations 29 confirmed the dissociative adsorption. The oval depression aligning in the [100] direction, shown in Figure 2c, is considered to be two oxygen atoms adsorbed at hollow sites separated by 2a 0 .…”

Generating and optimizing the catalytic activity in UiO-66 for aerobic oxidation of alkenes by post-synthetic exchange Ti atoms combined with ligand substitution

“…37 This strategy has been used, for instance, to increase the photocatalytic activity of parent UiO-66(Zr) for CO2 reduction by introducing Ti 4+ acting as electron relay between photoexcited terephthalate ligand and Zr 4+ . 38 To check this concept, and considering the known activity of Ti 4+ grafted on mesoporous silicas and zeolites as oxidation catalysts, particularly in the presence of peroxides as oxidizing reagents, but also using oxygen as terminal oxidant, [39][40][41][42][43][44][45] in the present study we have focused on the reactivity of alkenes, particularly, cycloalkenes, to form the corresponding epoxide or allylic ol/one mixtures. The novelty of our study derives from the consideration that, as it will be described below, UiO-66(Zr) is devoid of any significant activity in the aerobic oxidation of cycloalkenes, but by applying known chemistry in the field of zeolites and aluminum silicates grafting Ti 4+ it is possible to introduce active sites to promote this aerobic oxidation.…”