Adsorption and coadsorption of carbon monoxide and hydrogen on Pd(111)

Кискинова, М.; Bliznakov, G.

doi:10.1016/0039-6028(82)90129-7

Cited by 108 publications

(26 citation statements)

References 38 publications

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“…The rate coefficient of CO desorption from the noble metal (backward reaction in step 1) is very low in the present study compared to the value reported by Nibbelke et al [1]. This is notably due to the difference in the noble metal used, and such phenomenon has been observed by other researchers [37][38][39], where it is reported that desorption of CO from Pd is slowly occurring around 480 K, while CO desorption from Pt readily occurs at much lower temperatures. This slow rate of CO desorption from the noble metal has an effect on the surface reaction between CO and oxygen on noble metal (step 4), since a lower rate coefficient is found for the present catalyst.…”

Section: Co Oxidation By O 2 In the Absence Of H 2 O And Cocontrasting

confidence: 76%

Transient kinetics of carbon monoxide oxidation by oxygen over supported palladium/ceria/zirconia three-way catalysts in the absence and presence of water and carbon dioxide

Rajasree

Hoebink

Schouten

2004

Journal of Catalysis

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Section: Co Oxidation By O 2 In the Absence Of H 2 O And Cocontrasting

confidence: 76%

Transient kinetics of carbon monoxide oxidation by oxygen over supported palladium/ceria/zirconia three-way catalysts in the absence and presence of water and carbon dioxide

Rajasree

Hoebink

Schouten

2004

Journal of Catalysis

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“…Specific carbon atoms are denoted, where possible. is at about 490 K, consistent with CO production being desorption limited [19]. The relatively small saturation yield of CO (0.12 ML) suggests that only a relatively small coverage of GBL (maximum of 0.06 ML) undergoes complete decarbonylation.…”

Section: Temperature Programmed Desorptionsupporting

confidence: 64%

“…The relatively small saturation yield of CO (0.12 ML) suggests that only a relatively small coverage of GBL (maximum of 0.06 ML) undergoes complete decarbonylation. The hydrogen (m/e = 2) desorption trace contains a major peak with a maximum at about 350 K, which is consistent with H 2 also arising from a desorption-limited process [19,20]. There appears to be a shoulder and long trailing edge in the H 2 desorption trace, suggesting that some additional surface dehydrogenation reactions occur at higher temperature.…”

Section: Temperature Programmed Desorptionsupporting

confidence: 51%

Adsorption and decomposition of γ-butyrolactone on Pd(111) and Pt(111)

Horiuchi¹,

Medlin²

2010

Surface Science

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“…40 From a simple Langmuir argument a second-order adsorption is expected, but the observed adsorption data from studies on single-crystalline Pd surfaces indicate that the sticking coefficient is much less dependent on the hydrogen coverage. 41,42 The adsorption order on Pd films is not clear from the literature, but here we will show that a second-order adsorption, as used above, is appropriate. Figure 2 shows the HD desorption from a Pd surface at a certain pressure for temperatures in the range of 223-523 K. The surface is exposed to a mixture of H 2 and D 2 and HD is formed on the Pd surface after dissociation of the impinging molecules.…”

Section: B Experimental Evidence For Second-order Adsorptionmentioning

confidence: 76%

“…The reason to include x = 0.5 is that it "simulates" the observed precursor adsorption observed on single-crystalline Pd. 41,42 We expect that the hydrogen coverages from the two types of experiments are equal ͑solid line͒ and observed that the best agreement is obtained for x = 2. The conclusion is therefore that the hydrogen sticking is of second order for hydrogen adsorption on the Pd surface ͑at least for s Ͻ 0.6͒.…”

Section: B Experimental Evidence For Second-order Adsorptionmentioning

confidence: 98%

Hydrogen interaction with platinum and palladium metal–insulator–semiconductor devices

Salomonsson

Eriksson

Dannetun

2005

Journal of Applied Physics

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Application of polymer-coated metal-insulator-semiconductor sensors for the detection of dissolved hydrogenComparative hydrogen sensing performances of Pd-and Pt-InGaP metal-oxide-semiconductor Schottky diodes Bridging the pressure gap for palladium metal-insulator-semiconductor hydrogen sensors in oxygen containing environments J. Appl. Phys. 84, 44 (1998); 10.1063/1.368000 Hydrogen adsorption states at the Pd/SiO 2 interface and simulation of the response of a Pd metal-oxide-semiconductor hydrogen sensor Hydrogen-sensitive Pd-SiO 2 -Si and Pt-SiO 2 -Si metal-insulator-semiconductor ͑MIS͒ devices have been studied in ultrahigh vacuum in the temperature range of 223-523 K. Adsorption/ absorption of hydrogen occurs at the metal surface, in the metal bulk, and at the metal-insulator interface. The sensor signal, caused by hydrogen adsorption at the interface, shows a logarithmic dependence on the applied hydrogen pressure. The Pt-MIS device, which is fully functional at atmospheric pressures, is sensitive to changes in hydrogen pressure down to the 10 −12 -Torr scale. We propose that the interface adsorption follows a so-called Temkin isotherm with an interface heat of adsorption that varies with hydrogen coverage as ⌬H i0 ͑1−a͒. The initial heat of adsorption ⌬H i0 is determined to 0.78 eV/ hydrogen atom. The adsorption potential at the external Pt surface is found to be 0.45 eV/ hydrogen atom. These values were obtained by modeling the hydrogen interaction with the MIS devices and fitting the model to a number of experimental results. Also studies of Pd-based devices were performed and compared with Pt. The hydrogen adsorption on the metal surface, previously treated as a first-order process on Pd, is shown to follow a second-order process. Qualitatively the results from the Pd-and Pt-MIS devices agree. Quantitatively there are differences. The hydrogen sensitivity of the Pt-MIS device is only approximately one-third compared to that of the Pd-MIS structure. This agrees with the result that the concentration of available hydrogen adsorption sites at the Pt-SiO 2 interface is approximately 7 ϫ 10 17 m −2 whereas the concentrations of sites at the Pd-SiO 2 interface is roughly three times larger ͑2 ϫ 10 18 m −2 ͒. An estimate of the size of the dipole moments ͑0.6-0.7 D͒ implies that the interface hydrogen atoms are strongly polarized. Differences are also observed in the microstructure of the metal films. Atomic force microscopy results show that the Pd surface reconstructs during H 2 -O 2 exposures, while the Pt surface shows no such change at these temperatures.

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Adsorption and coadsorption of carbon monoxide and hydrogen on Pd(111)

Cited by 108 publications

References 38 publications

Transient kinetics of carbon monoxide oxidation by oxygen over supported palladium/ceria/zirconia three-way catalysts in the absence and presence of water and carbon dioxide

Transient kinetics of carbon monoxide oxidation by oxygen over supported palladium/ceria/zirconia three-way catalysts in the absence and presence of water and carbon dioxide

Adsorption and decomposition of γ-butyrolactone on Pd(111) and Pt(111)

Hydrogen interaction with platinum and palladium metal–insulator–semiconductor devices

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