Oxygen-adsorption induced reconstruction of Cu(110) studied by high energy ion scattering

Feidenhans’l, R.; Stensgaard, I.

doi:10.1016/0039-6028(83)90013-4

Cited by 101 publications

(6 citation statements)

References 24 publications

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“…Oxygen chemisorption on Cu(110) is a model system which has been studied extensively [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Molecular oxygen is known to dissociatively chemisorb on Cu(110) and results in a (21) "added-row" structure, in which the oxygen adatoms reside preferentially in the long-bridge (LB) sites of every other [001] rows of the Cu lattice [3][4][5][18][19][20][21]. The nucleation and growth of the (21) reconstruction have been assumed to occur via the following two steps [20][21][22]: i) Cu atoms detach from step edges and diffuse out on the terraces, ii) interaction of diffusing Cu adatoms with oxygen atoms impinging from the gas phase results in the anisotropic growth on the terraces of -Cu-Oadded rows aligned parallel to the [001] direction of the Cu substrate.…”

Section: Introductionmentioning

confidence: 99%

Role of oxygen in Cu(1 1 0) surface restructuring in the vicinity of step edges

Cai

Saidi

et al. 2014

Chemical Physics Letters

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Surface steps are typically assumed as a source of adatoms for oxygen-chemisorption induced surface reconstruction, but few microscopic observations have been made in the vicinity of steps on reconstructing surfaces. Using in-situ scanning tunneling microscopy, we provide direct evidence that surface steps are the source of Cu adatoms for the Cu(110)-(21)-O restructuring. Using density functional theory, we show that the role of oxygen is to stabilize Cu adatoms detached from step edges via the barrier-less formation of Cu-O dimers on terraces. Incorporating this atomic process of capturing Cu adatoms into kinetic Monte Carlo simulations reproduces the experimentally observed (2×1)-O reconstruction.

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Section: Introductionmentioning

confidence: 99%

Role of oxygen in Cu(1 1 0) surface restructuring in the vicinity of step edges

Cai

Saidi

et al. 2014

Chemical Physics Letters

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“…The dramatic drop of the O-sticking coefficient when increasing the O-coverage from 0.5 ML of the O-(2x1) adlayer to the 0.67 ML of the O-c(6x2) adlayer should result in the observed oxygen saturation effect. 36 Therefore, we use the O 1s saturation intensity level as the reference for 0.5 ML. The reproducibility was tested by following the O 1s: Cu 3p intensity ratio obtained in different calibration experiments.…”

Section: Methodsmentioning

confidence: 99%

Adsorbate coverages and surface reactivity in methanol oxidation over Cu(110): An in situ photoelectron spectroscopy study

Günther

Zhou

Hävecker

et al. 2006

The Journal of Chemical Physics

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The adsorbate species present during partial oxidation of methanol on a Cu(110) surface have been investigated in the 10 -5 mbar range with in situ x-ray photoelectron spectroscopy (XPS) and rate measurements. Two reaction intermediates were identified, methoxy with a C 1s binding energy (BE) of 285.4 eV and formate with a C 1s BE of 287.7 eV. The c(2x2) overlayer formed under reaction conditions is assigned to formate. Two states of adsorbed oxygen were found characterized by O 1s BE's of 529.6 and 528.9 eV, respectively. On the inactive surface present at low T around 300 -350 K formate dominates while methoxy is almost absent. Ignition of the reaction correlates with a decreasing formate coverage. A large hysteresis of ≈ 200 K width occurs in T-cycling experiments whose correlation with adsorbate species was studied with varying oxygen and methanol partial pressures. The two branches of the hysteresis differ mainly in the amount of adsorbed oxygen, the methoxy species and a carbonaceous species. Methoxy covers only a minor part of the catalytic surface reaching at most 20%. Above 650 K the surface is largely adsorbate free.

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“…The chemisorption of oxygen on Cu(110) has been investigated in numerous experimental − and theoretical − studies. Oxygen adsorbs dissociatively on Cu(110) at room temperature (RT).…”

Section: Introductionmentioning

confidence: 99%

“…Cu atoms dissolve from the step edges even at RT, diffuse on terraces, and then trap oxygen adatoms. At exposures above ∼10 5 L, which correspond to ∼10 19 molecules · cm −2 , formation of the c (6 × 2)-O phase is induced at RT. , After further oxygen exposures, Cu 2 O formation has been observed on Cu(110). , However, temperatures above 480 K are required for desorbing the adsorbed oxygen …”

Section: Introductionmentioning

confidence: 99%

Kinetics of Oxygen Adsorption and Initial Oxidation on Cu(110) by Hyperthermal Oxygen Molecular Beams

et al. 2009

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Oxygen adsorption and subsequent oxide formation on Cu(110) using a hyperthermal oxygen molecular beam (HOMB) were investigated using X-ray photoelectron spectrometry. The O-uptake curves, which were determined from the evolution of the O-1s peaks, indicate that simple Langmuir type kinetics can describe dissociative adsorption of O(2) with an incident energy (E(i)) below 0.5 eV under Theta < or = 0.5 ML. The reaction order dependence on E(i) implies two competing dissociation mechanisms, trapping-mediated and directly activated adsorption. Oxidation at Theta > or = 0.5 ML proceeds rather effectively using highly energetic HOMB at E(i) > or = 1.0 eV. The azimuthal dependence of the sticking probability during the effective oxidation using HOMB incidence suggests that the added rows, which consist of the Cu-O structure, shade the reactive hollow sites in the trough where oxygen penetrates into the subsurface. The surface Cu(2)O formed with highly energetic HOMB incidence decomposes with desorbing subsurface oxygen even at room temperature, demonstrating that HOMB can induce a metastable surface structure that cannot be produced in the thermal equilibrium process.

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Oxygen-adsorption induced reconstruction of Cu(110) studied by high energy ion scattering

Cited by 101 publications

References 24 publications

Role of oxygen in Cu(1 1 0) surface restructuring in the vicinity of step edges

Role of oxygen in Cu(1 1 0) surface restructuring in the vicinity of step edges

Adsorbate coverages and surface reactivity in methanol oxidation over Cu(110): An in situ photoelectron spectroscopy study

Kinetics of Oxygen Adsorption and Initial Oxidation on Cu(110) by Hyperthermal Oxygen Molecular Beams

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