FTIR investigation under reaction conditions during CO oxidation over Ru(x)-CeO2 catalysts

The synergistic effect of cyclohexane and cyclohexanone promoted synthesis of adipic acid catalyzed by [MnIIIT(p-Cl)PP]Cl with cyclohexane and cyclohexanone as co-reactants. The results showed that the conversions of cyclohexane and cyclohexanone were significantly enhanced because of the cyclohexanone synergistic effect, and the higher selectivity to adipic acid was obtained with dioxygen as an oxidant. The studies indicated that the co-oxidation of cyclohexane and cyclohexanone was influenced by the initial molar ratio of cyclohexanone and cyclohexane, catalyst structure, catalyst concentrations, and reaction conditions. The preliminary mechanism of the co-oxidation reaction of cyclohexane and cyclohexanone using [MnIIIT(p-Cl)PP]Cl as the catalyst was proposed.

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Clarifying the impacts of surface hydroxyls on CO oxidation on CeO2(100) surfaces: a DFT+U study

Physical Chemistry Chemical Physics ◽

10.1039/d0cp00204f ◽

2020 ◽

Vol 22 (15) ◽

pp. 7738-7746

Author(s):

Hui Zhou ◽

Dong Wang ◽

Xue-Qing Gong

Keyword(s):

Heterogeneous Catalysis ◽

Co Oxidation ◽

Common Phenomenon ◽

Reaction Conditions ◽

Surface Hydroxyls ◽

Surface Hydroxylation

In heterogeneous catalysis, surface hydroxylation is well recognized as a common phenomenon under realistic reaction conditions.

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CO Oxidation on Stepped Rh Surfaces: μm-Scale Versus Nanoscale

Catalysis Letters ◽

10.1007/s10562-019-02950-0 ◽

2019 ◽

Vol 150 (3) ◽

pp. 605-612 ◽

Cited By ~ 2

Author(s):

Y. Suchorski ◽

I. Bespalov ◽

J. Zeininger ◽

M. Raab ◽

M. Datler ◽

...

Keyword(s):

Co Oxidation ◽

Oxidation Reaction ◽

Active Surface ◽

Reaction Conditions ◽

Miller Index ◽

Co Oxidation Reaction ◽

Catalytically Active ◽

Field Emission Microscopy ◽

Photoemission Electron

Abstract The catalytic CO oxidation reaction on stepped Rh surfaces in the 10−6 mbar pressure range was studied in situ on individual μm-sized high-Miller-index domains of a polycrystalline Rh foil and on nm-sized facets of a Rh tip, employing photoemission electron microscopy (PEEM) and field-ion/field-emission microscopy (FIM/FEM), respectively. Such approach permits a direct comparison of the reaction kinetics for crystallographically different regions under identical reaction conditions. The catalytic activity of the different Rh surfaces, particularly their tolerance towards poisoning by CO, was found to be strongly dependent on the density of steps and defects, as well as on the size (µm vs. nm) of the respective catalytically active surface. Graphic Abstract

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Combining Planar Laser-Induced Fluorescence with Stagnation Point Flows for Small Single-Crystal Model Catalysts: CO Oxidation on a Pd(100)

Catalysts ◽

10.3390/catal9050484 ◽

2019 ◽

Vol 9 (5) ◽

pp. 484 ◽

Cited By ~ 1

Author(s):

Jianfeng Zhou ◽

Sebastian Matera ◽

Sebastian Pfaff ◽

Sara Blomberg ◽

Edvin Lundgren ◽

...

Keyword(s):

Single Crystal ◽

Co Oxidation ◽

Flow Reactor ◽

Laser Induced Fluorescence ◽

Model Catalysts ◽

Stagnation Flow ◽

Reaction Conditions ◽

Planar Laser Induced Fluorescence ◽

Planar Laser ◽

Crystal Model

A stagnation flow reactor has been designed and characterized for both experimental and modeling studies of single-crystal model catalysts in heterogeneous catalysis. Using CO oxidation over a Pd(100) single crystal as a showcase, we have employed planar laser-induced fluorescence (PLIF) to visualize the CO2 distribution over the catalyst under reaction conditions and subsequently used the 2D spatially resolved gas phase data to characterize the stagnation flow reactor. From a comparison of the experimental data and the stagnation flow model, it was found that characteristic stagnation flow can be achieved with the reactor. Furthermore, the combined stagnation flow/PLIF/modeling approach makes it possible to estimate the turnover frequency (TOF) of the catalytic surface from the measured CO2 concentration profiles above the surface and to predict the CO2, CO and O2 concentrations at the surface under reaction conditions.

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Preferential CO oxidation in hydrogen (PROX) on ceria-supported catalysts, part II: Oxidation states and surface species on Pd/CeO2 under reaction conditions, suggested reaction mechanism

Journal of Catalysis ◽

10.1016/j.jcat.2005.10.015 ◽

2006 ◽

Vol 237 (1) ◽

pp. 17-28 ◽

Cited By ~ 142

Author(s):

O POZDNYAKOVA ◽

D TESCHNER ◽

A WOOTSCH ◽

J KROHNERT ◽

B STEINHAUER ◽

...

Keyword(s):

Reaction Mechanism ◽

Co Oxidation ◽

Supported Catalysts ◽

Oxidation States ◽

Surface Species ◽

Reaction Conditions ◽

Preferential Co Oxidation

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Surface science under reaction conditions: CO oxidation on Pt and Pd model catalysts

Chemical Society Reviews ◽

10.1039/c7cs00045f ◽

2017 ◽

Vol 46 (14) ◽

pp. 4347-4374 ◽

Cited By ~ 76

Author(s):

Matthijs A. van Spronsen ◽

Joost W. M. Frenken ◽

Irene M. N. Groot

Keyword(s):

Ir Spectroscopy ◽

Co Oxidation ◽

Surface Science ◽

Catalytic Reactions ◽

Model Catalysts ◽

Chemical Information ◽

Reaction Conditions ◽

P Application

Application of surface-science techniques, such as XPS, SXRD, STM, and IR spectroscopy under catalytic reactions conditions yield new structural and chemical information. Recent experiments focusing on CO oxidation over Pt and Pd model catalysts were reviewed.

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Stroboscopic operando spectroscopy of the dynamics in heterogeneous catalysis by event-averaging

10.21203/rs.3.rs-136815/v1 ◽

2021 ◽

Author(s):

Jan Knudsen ◽

Tamires Gallo ◽

Virgínia Boix ◽

Marie Strømsheim ◽

Giulio D'Acunto ◽

...

Keyword(s):

Co Oxidation ◽

Photoelectron Spectroscopy ◽

Oxidation Reaction ◽

Ambient Pressure ◽

Reaction Conditions ◽

Catalyst Structure ◽

Time Resolved ◽

Co Oxidation Reaction ◽

Surface Phases ◽

Gas Environment

Abstract Heterogeneous catalyst surfaces are highly dynamic entities that respond rapidly to changes in their local gas environment, and the dynamics of the response is a decisive factor for the catalysts’ action and activity. Few probes are able to map catalyst structure and local gas environment simultaneously under reaction conditions at the time scales of the dynamic changes. Here we use the CO oxidation reaction over a Pd(100) surface exposed to pressures of 3 and 100 mbar of a CO + O2 gas mixture to demonstrate how such studies can be performed by time-resolved ambient pressure photoelectron spectroscopy. Central elements of the method are cyclic gas pulsing and software-based event-averaging by image recognition of spectral features. For the CO oxidation reaction over Pd(100) our main finding is that that all surface phases – the CO-covered Pd surface, a surface oxide and a thick PdOx phase – catalyse the CO oxidation reaction, in dependence on the supply of gas phase reactants.

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