Path and mechanism of hydrogen absorption at Pd(100)

Okuyama, Hiroshi; Siga, W.; Takagi, Noriaki; Nishijima, Michiharu; Aruga, Tetsuya

doi:10.1016/s0039-6028(98)00020-x

Cited by 158 publications

(144 citation statements)

References 30 publications

Supporting

Mentioning

130

Contrasting

Unclassified

Order By: Relevance

“…It was concluded that the accessibility of subsurface hydrogen should be the key parameter governing the hydrogenation. Hydrogen/deuterium TDS measurements [20,35,[49][50][51] on different palladium surfaces reveal a rather general pattern for hydrogen species, with differences on the order of a factor of 2-10 in the ad(ab)sorption capacity. The presence or absence of different hydrogen species was mainly governed by the amount and temperature of hydrogen exposure and the prehistory of the samples.…”

Section: Discussionmentioning

confidence: 97%

High-pressure X-ray photoelectron spectroscopy of palladium model hydrogenation catalysts. Part 2: Hydrogenation of trans-2-pentene on palladium

Teschner

Pestryakov

Kleimenov

et al. 2005

Journal of Catalysis

View full text Add to dashboard Cite

We have performed the first "high-pressure" XPS study on the palladium, hydrogen and olefin (trans-2-pentene) system in order to gain a better insight into the hydrogenation reaction. We report here data collected using a Pd(111) single crystal and a polycrystalline foil. Hydrogenation was observed on polycrystalline foil (RT and 373 K), but not on Pd(111) single crystal, revealed by on-line mass-spectrometry. We observed the reaction in the presence of huge amount of carbon (up to 73 %) in the information depth of XPS. On Pd(111) mainly graphite was present while other components C-H and C-Pd were also formed on the foil in much higher extent. C-Pd characterizes a carbon species in the interaction with palladium whereas C-H represents hydrogenated carbon including chemisorbed species. The d-band of the foil showed a remarkable up-shift towards E FERMI as compared to Pd(111). We concluded that both differences found in the valence and in C 1s region are indicators for different electronic structures that contribute to the variation in activity. The palladium foil lost its activity at elevated temperature (523 K), most probably due to desorption of hydrogen. Using additional UPS measurements we concluded that trans-2-pentene is hydrogenated in σ-bonded chemisorption modus, at least in UHV conditions.

show abstract

Section: Discussionmentioning

confidence: 97%

High-pressure X-ray photoelectron spectroscopy of palladium model hydrogenation catalysts. Part 2: Hydrogenation of trans-2-pentene on palladium

Teschner

Pestryakov

Kleimenov

et al. 2005

Journal of Catalysis

View full text Add to dashboard Cite

show abstract

“…12,19,20 1. Dissociative and molecular chemisorption onto the catalyst surface A. Hydrogen dissociative chemisorption [21][22][23][24][25] At the equilibrium,…”

Section: 17mentioning

confidence: 99%

Determination of mass transfer resistances of fast reactions in three‐phase mechanically agitated slurry reactors

Stamatiou

Muller

2016

AIChE Journal

View full text Add to dashboard Cite

A methodology for the determination of mass transfer resistances of fast reactions in three-phase mechanically agitated slurry reactors under the reaction conditions is presented. The mass transfer resistances affect significantly the overall mass transfer rate, the design equation and consequently the scale up of the reactor. There is not established methodology to separate the mass transfer resistances under reaction conditions by changing catalyst loading and manipulating the process variables, pressure and agitation speed. This allows to avoid the use of different catalyst particles and give the chance to calculate the mass transfer resistances without caring about the type of catalyst. We calculate each mass transfer resistance under conditions which do not allow to neglect any of the resistances. It is shown that the level off of mass transfer rate which is developed in the plot of mass transfer rate against agitation speed plots is not enough to determine the limiting regime. The hydrogenation of styrene over Pd/C (5% catalyst content) is used as case study to demonstrate the methodology.

show abstract

“…13 and 14. The P-C isotherms of the Pd NPs (4.1 nm) shows the significant decrease of the hydrogen solubility in the α-phase after the 1st hydrogen absorption due to the strong binding for H atoms on the Pd surfaces and subsurfaces [1][2][3][4][5][6]. The isotherm of the 2nd hydrogen absorption of the Pd NPs (4.1 nm) shows the bulk-like plateau region at ∼ 15 Torr.…”

Section: B the Size Dependence Of The Hydrogen Absorptionmentioning

confidence: 98%

“…The H 2 molecule dissociates into H atoms on the Pd surface. The H atoms are bound strongly at the hollow sites of the Pd surface even if at the room temperature [1][2][3][4][5][6]. After the adsorption on the surface, the H atom can penetrate into octahedral interstitial site of the Pd bulk via the subsurface sites.…”

Section: Introductionmentioning

confidence: 99%

“…The Pd is the ideal material for the investigation of the fundamentals of the hydrogenation because of the high reactivity and the resistance against the oxidation. Many researchers have studied the morphology, thermodynamics and kinetics of the H-Pd system for more than three decades by the low energy electron diffraction (LEED), thermal desorption spectroscopy (TDS), electron energy loss spectroscopy (EELS), nuclear reaction analysis (NRA) and so on [1][2][3][4][5][6].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hydrogen Storage Property of the Pd Nanoparticle with Clean Surfaces Studied by QCM

Ogawa

Fujimoto

Kanai³

et al. 2015

e-J. Surf. Sci. Nanotech.

View full text Add to dashboard Cite

The hydrogen absorption behavior of the Pd NPs has been investigated by the noble techniques. The Pd NPs with the clean surface have been fabricated by the gas evaporation method. The P-C isotherm of the hydrogen absorption of the Pd NPs has been obtained using the QCM without the exposure to the air. The P-C isotherms have shown the clear size dependent absorption behavior for the Pd NPs. Further absorption and desorption cycles decrease the solubility of H significantly in the Pd NPs.

show abstract

Path and mechanism of hydrogen absorption at Pd(100)

Cited by 158 publications

References 30 publications

High-pressure X-ray photoelectron spectroscopy of palladium model hydrogenation catalysts. Part 2: Hydrogenation of trans-2-pentene on palladium

High-pressure X-ray photoelectron spectroscopy of palladium model hydrogenation catalysts. Part 2: Hydrogenation of trans-2-pentene on palladium

Determination of mass transfer resistances of fast reactions in three‐phase mechanically agitated slurry reactors

Hydrogen Storage Property of the Pd Nanoparticle with Clean Surfaces Studied by QCM

Contact Info

Product

Resources

About