Formation of Ru subcarbonyls by reaction of CO with stepped Ru single crystal surfaces

Kruse, Norbert

doi:10.1016/0039-6028(86)90357-2

Cited by 32 publications

(8 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The present PFDMS results prove such Co-subcarbonyls to be formed indeed. Previous studies of carbonyl formation on metals like Ni, Ru or Rh [5,7,16,17] have demonstrated carbonyls to be mobile and likely involved in morphological shape transformations. Future studies by PFDMS will address the question for a possible Co(CO) x,ad mobility.…”

Section: Resultsmentioning

confidence: 99%

“…With this background, it appears challenging to examine whether proven concepts of metal-organic chemistry can be applied to metal surfaces as well. For example, the formation of adsorbed metal-subcarbonyls was reported for a number of metals including Ni [5], Co [6] and Ru [7] but despite earlier claims [8] the possible role of such species in the hydrocarbon chain growth mechanism remains unknown at present.…”

Section: Introductionmentioning

confidence: 96%

See 1 more Smart Citation

Catalytic CO Hydrogenation: Mechanism and Kinetics from Chemical Transients at Low and Atmospheric Pressures

et al. 2008

View full text Add to dashboard Cite

The hydrogenation of CO over Co model catalysts was studied using relaxation-type methods operating in situ either at atmospheric pressures or under surface science conditions. Emphasis was laid on providing information on the surface composition and on how it changes with time under catalytic reaction conditions. Using pressure forcing in chemical transient kinetics (CTK), the build-up of the steady-state was studied at 503 K and atmospheric pressure to demonstrate that the active catalyst surface is not metallic but covered with carbon, oxygen and hydrogen in excess of a monolayer equivalent. Both buildup and backward transients suggest CO to act as the ''monomer'' which probably inserts into an O-H bond to form the primary surface complex necessary for hydrocarbon and oxygenate formation. Repetitive electric field pulses (pulsed field desorption mass spectrometry, PFDMS) at low pressures have allowed the CO dissociation kinetics on a nano-sized Co 3D crystal (''tip'') to be monitored in the millisecond time range. No evidence for the occurrence of the Boudouard reaction was obtained in either PFDMS or CTK. Adsorbed CH x (x = 1-3) species were detected in small amounts demonstrating that CO dissociation is fast compared to carbon hydrogenation. Adsorbed Co-subcarbonyl species, Co(CO) x were also detected by PFDMS and possibly mediate the necessary surface mobility during the initial restructuring of the catalyst. Surface carbon seems to inhibit Co-subcarbonyl formation.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 96%

Catalytic CO Hydrogenation: Mechanism and Kinetics from Chemical Transients at Low and Atmospheric Pressures

et al. 2008

View full text Add to dashboard Cite

show abstract

“…It was previously demonstrated see, for example, Ref. [8] that a systematic variation of the pulse field strength can reveal whether or not diffusion is in operation. Usually, high field strengths can suppress the influence of long-range diffusion from the shank of the tip into the crystal apex region.…”

Section: Resultsmentioning

confidence: 97%

Formation of N2O and (NO)2 During NO Adsorption on Au 3D Crystals

2004

Self Cite

View full text Add to dashboard Cite

The adsorption of NO on Au 3D hemispherical crystals (''field emitter tips'') has been studied by means of pulsed field desorption mass spectrometry (PFDMS) under dynamic gas flow conditions and at 300 K. Local chemical probing of $200 Au sites in the stepped surface region between the central (111) pole and the peripheral (001) plane leads to the detection of NO þ , N 2 O þ and (NO) þ 2 species. Obviously, molecular NO adsorption on stepped Au surfaces can lead to dimerization. Nitrous oxide formation probably occurs via the dimer, (NO) 2 .

show abstract

“…Probably the most detailed kinetic information on surface reactions available at present is that of carbonyl formation on transition metals such as Ni [104], Co [105], Ru [106], Pd [107] and Rh [100]. Some of them have since been overcome, for example, by using synchrotron radiation, but others are inherent to the method.…”

Section: B Kinetics and Mechanisms As Measured By Local Probe Methodsmentioning

confidence: 99%

Heterogeneous Catalysis and High Electric Fields

Kruse

Bocarmé

2008

Handbook of Heterogeneous Catalysis

View full text Add to dashboard Cite

Introduction The relationships between high electric fields and heterogeneous catalysis are twofold: First, high electric fields are applied in field emission and field ion microscopes and related methods. These techniques can provide detailed in situ information on catalytic surface processes with a lateral resolution on the atomic scale. Second, high electric fields can affect the surface properties of solids. Electronic and structural parameters are frequently field dependent and influence chemisorption processes of molecules and also catalytic activity and reaction pathways of surface reactions.High electric fields, defined as fields of the order of some tens of volts per nanometer, are what valence electrons in atoms and molecules experience and what these electrons are exposed to on adsorption at solid surfaces. Thus, these fields are ubiquitous in chemistry and form, in the context of this contribution, an intimate part of heterogeneous catalysis. Quantum mechanical aspects of chemical bonding of solid surfaces distinguish between shortrange covalent and long-range electrostatic contributions. These long-range effects create an electrostatic Coulomb potential which causes changes in ionization potentials and electron affinities of adsorbed molecules. As a consequence, catalytic surface reactions may be altered. However, in real catalysts it is sometimes difficult to distinguish between contributions of local binding and long-range electrostatic fields.Long-range fields of the order of 10 V nm −1 are generated in a controlled manner in the field ion microscope, originally developed by Muller [1] for imaging * Corresponding author.

show abstract

Formation of Ru subcarbonyls by reaction of CO with stepped Ru single crystal surfaces

Cited by 32 publications

References 21 publications

Catalytic CO Hydrogenation: Mechanism and Kinetics from Chemical Transients at Low and Atmospheric Pressures

Catalytic CO Hydrogenation: Mechanism and Kinetics from Chemical Transients at Low and Atmospheric Pressures

Formation of N2O and (NO)2 During NO Adsorption on Au 3D Crystals

Heterogeneous Catalysis and High Electric Fields

Contact Info

Product

Resources

About