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Appel, Lucia G.; Eon, Jean‐Guillaume; Schmal, Martín

doi:10.1023/a:1019098121432

Cited by 74 publications

(47 citation statements)

References 11 publications

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“…4 shows the DRIFT spectra of CO 2 and CO adsorbed on 1 wt.% Pt/CeO 2 . When CO 2 is exposed to Pt/CeO 2 on the DRIFT Procedure B, the absorption peaks assigned to the hydrogenocarbonate species were observed at around 1630, 1350 and 1060 cm À1 [20][21][22], and the absorption peaks assigned to the monodentate carbonate species were observed at 1520 and 1270 cm À1 [21][22][23][24]. The intensities of these peaks were much higher than those observed for the CO adsorption treatment in Fig.…”

Section: Evaluation Of Precious Metal Dispersions On Ceo 2 -Zromentioning

confidence: 73%

“…Moreover, the other peaks assigned to the hydrogenocarbonate species appeared at ca. 1630 and 1270 cm À1 [20][21][22], and the peak assigned to the monodentate carbonate species appeared at ca. 1520 cm À1 [21][22][23][24].…”

Section: Evaluation Of Precious Metal Dispersions On Ceo 2 -Zromentioning

confidence: 99%

“…1630 and 1270 cm À1 [20][21][22], and the peak assigned to the monodentate carbonate species appeared at ca. 1520 cm À1 [21][22][23][24]. These infrared bands indicated that CO was adsorbed not only on the surface atoms of the Pt particles but also on the CeO 2 support as carbonate species.…”

Section: Evaluation Of Precious Metal Dispersions On Ceo 2 -Zromentioning

confidence: 99%

See 2 more Smart Citations

Determination of dispersion of precious metals on CeO2-containing supports

Takeguchi

Manabe

Kikuchi

et al. 2005

Applied Catalysis A: General

149

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Section: Evaluation Of Precious Metal Dispersions On Ceo 2 -Zromentioning

confidence: 73%

Section: Evaluation Of Precious Metal Dispersions On Ceo 2 -Zromentioning

confidence: 99%

See 1 more Smart Citation

Determination of dispersion of precious metals on CeO2-containing supports

Takeguchi

Manabe

Kikuchi

et al. 2005

Applied Catalysis A: General

149

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“…These studies have also observed the presence of surface-bound formate species under reaction conditions [16] and also have measured the stability of these species in inert gas and hydrogen [17,18]. Compared with single crystal copper surfaces, the surface species observed on the oxide supported polycrystalline copper system are more complex because of the multi-faceted copper surfaces presented by the supported particles [14,17,[19][20][21] and the presence of species adsorbed on the support materials (e.g., alumina and ceria) as well as the support-metal interface [22]. More complex infrared spectra are observed which makes assignment more difficult than on the single crystals [23][24][25].…”

Section: Introductionmentioning

confidence: 99%

Isotope Effects in Methanol Synthesis and the Reactivity of Copper Formates on a Cu/SiO2 Catalyst

et al. 2008

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Here we investigate isotope effects on the catalytic methanol synthesis reaction and the reactivity of copper-bound formate species in CO 2 -H 2 atmospheres on Cu/SiO 2 catalysts by simultaneous IR and MS measurements, both steady-state and transient. Studies of isotopic variants (H/D, 12 C/ 13 C) reveal that bidentate formate dominates the copper surface at steady state. The steadystate formate coverages of HCOO (in 6 bar 3:1 H 2 :CO 2 ) and DCOO (in D 2 :CO 2 ) are similar and the steady-state formate coverages in both systems decrease by *80% from 350 K to 550 K. Over the temperature range 413 K-553 K, the steady-state methanol synthesis rate shows a weak H/D isotope effect (1.05 ± 0.05) with somewhat higher activation energies in H 2 :CO 2 (79 kJ/mole) than D 2 :CO 2 (71 kJ/mole) over the range 473 K-553 K. The reverse water gas shift (RWGS) rates are higher than methanol synthesis and also shows a weak positive H/D isotope effect with higher activation energy for H 2 /CO 2 than D 2 /CO 2 (108 vs. and 102 kJ/mole) The reactivity of the resulting formate species in 6 bar H 2 , 6 bar D 2 and 6 bar Ar is strongly dominated by decomposition back to CO 2 and H 2 . H 2 and D 2 exposure compared to Ar do not enhance the formate decomposition rate. The decomposition profiles on the supported catalyst deviate from first order decay, indicating distributed surface reactivity. The average decomposition rates are similar to values previously reported on single crystals. The average activation energies for formate decomposition are 90 ± 17 kJ/mole for HCOO and 119 ± 11 kJ/mole for DCOO. By contrast to the catalytic reaction rates, the formate decomposition rate shows a strong H/D kinetic isotope effect (H/D *8 at 413 K), similar to previously observed values on Cu(110).

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“…The presence of vacancies in rods and cubes is supported by the FTIR spectra in helium ( Figure 24) showing that the integrated intensity ratio of carbonates to OH groups in rods and cubes is significantly higher compared to that in octahedra. The formation of carbonates on ceria is due to the interaction with CO 2 from the ambient, resulting in the reduction of ceria to Ce 3+ and hence the creation of oxygen vacancies [141][142][143].…”

Section: Discussionmentioning

confidence: 99%