Interfacial properties of ZrO2 supported precious metal catalysts: A density functional study

Jung, Chang Ho; Ishimoto, Ryota; Tsuboi, Hideyuki; Koyama, Michihisa; Endou, Akira; Kubo, Momoji; Carpio, Carlos A. Del; Miyamoto, Akira

doi:10.1016/j.apcata.2006.02.050

Cited by 31 publications

(29 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The plot shows the direction of electron charge transfer, from Pt b atoms to CeO 2 surface and to Pt t atom. This charge transfer from Pt cluster to CeO 2 surface confirms the trends in charge transfer in previous works [50,53,54]. Moreover, we show that due to such charge transfer to Pt t and coupling with unpaired electrons of Pt t , the Pt t atom holds smaller spin moments as compared to the corresponding Pt atom of the isolated Pt 4 cluster.…”

Section: Pt 4 Cluster Adsorption On Ceo 2 (111)supporting

confidence: 90%

DFT+U study on the oxygen adsorption and dissociation on CeO2-supported platinum cluster

Escaño

Nakanishi

Kasai

et al. 2014

Applied Surface Science

View full text Add to dashboard Cite

We investigated the reactivity of CeO 2 -supported Pt 4 cluster (denoted as Pt 4 /CeO 2 (111)) towards O 2 adsorption and dissociation as well as the geometry/electronic properties associated with such metal oxide supported cluster system using Density Functional Theory and on-site Coulomb interaction correction via the Hubbard-like term, U (DFT+U). It was found that Pt 4 binds strongly to CeO 2 (111) via Pt-O-Ce bonds which act as "anchors" between the surface and the cluster, confirming its non-sintering as found in experiments. The adsorption of the cluster involves net electron transfer to CeO 2 , however, charge redistribution also happens within the cluster (from Pt atom bonded to the surface to the Pt on top of the cluster). This charge couples to the top Pt leading to reduce its spin moment as compared to that of unsupported cluster. When O 2 adsorbs on Pt 4 /CeO 2 (111), while it prefers Pt vertex site near the CeO 2 surface, the O-O bond elongation is more profound at the Pt-Pt edges. The energy barrier for dissociating O 2 from this edge site precursor state is smallest. A correlation between the O-O bond length at the precursor state and the stability at the transition state is revealed. Finally, the barrier for dissociation in unsupported Pt 4 is lower, indicating suppression of the cluster's reactivity due to the support. We 2 attribute this to the hybridization of Pt-5d orbitals with O-2p orbitals in CeO 2 (111) leading to the broadening of Pt-5d states near the Fermi level.

show abstract

Section: Pt 4 Cluster Adsorption On Ceo 2 (111)supporting

confidence: 90%

DFT+U study on the oxygen adsorption and dissociation on CeO2-supported platinum cluster

Escaño

Nakanishi

Kasai

et al. 2014

Applied Surface Science

View full text Add to dashboard Cite

show abstract

“…They found the adsorption of Pt to be associated with the largest surface rearrangement and strong Pt-Zr interaction as well as Pt-O bond formation. The same authors also report that oxidation of their clusters increased the metal-support interaction [62]. In addition, their calculations revealed a charge transfer from metal atoms in the clusters to the support and a polarization of the deposited clusters, consistent with our observed positive BE shifts.…”

Section: Morphological and Structural Characterizationsupporting

confidence: 89%

“…One possible interaction is the formation of interfacial Pt-Zr compounds. Jung et al [62] have studied the interfacial properties of ZrO 2-supported precious metals using DFT calculations for Pt 4 , Pd 4 , and Rh 4 clusters on the surface of ZrO 2 (111). They found the adsorption of Pt to be associated with the largest surface rearrangement and strong Pt-Zr interaction as well as Pt-O bond formation.…”

Section: Morphological and Structural Characterizationmentioning

confidence: 99%

Size-selected Pt Nanoparticles Synthesized via Micelle Encapsulation: Effect of Pretreatment and Oxidation State on the Activity for Methanol Decomposition and Oxidation

et al. 2009

View full text Add to dashboard Cite

The effect of pretreatment conditions on the oxidation state and activity of micelle-synthesized Pt nanoparticles supported on ZrO 2 was studied for methanol decomposition and oxidation reactions. An O 2 -pretreatment is observed to be effective for producing clean, stable, and active nanoparticles. Pt-oxide species formed during such pretreatments were found to have little influence in methanol decomposition reactions due to their tendency to reduce. However, these same species are stable during methanol oxidation and appear to take part in a Mars-van Krevelen-type of process, in which bound-oxygen (nanoparticle shell) may be replenished with oxygen from the gas phase.

show abstract

“…[2][3][4] Nowadays, the oxidation of VOC over supported noble metal (Pt, Pd or Rh) catalysts has been intensively studied. [5][6][7] But for their high prices and scarcity of noble metal, particular attention has been paid to the preparation and characterization of new, low-cost and efficient catalysts for the oxidation of VOC.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of New Material‐‐La/Zr/MMT Employed in Acetone Oxidation

et al. 2007

View full text Add to dashboard Cite

A new material of zirconium pillared montmorillonite added with lanthanum (denoted as La/Zr/MMT) was prepared for acetone oxidation. Surface properties of the catalysts were investigated by means of XRD, TEM, TG-DTA and BET methods. The XRD result indicated that the interlayer space of the montmorillonite was enlarged from 1.57 to 4.85 nm after the treatment with zirconium pillaring and the addition of lanthanum. N 2 adsorption-desorption result showed that by the process of zirconium pillaring, the specific surface area of the sample was increased to 128.0 m 2 /g, which was two times almost as large as pure montmorillonite. Simultaneously, the thermal stability was also enhanced. The activity of the new material on the total oxidation of acetone was investigated, and the results indicated that the catalytic activity of the montmorillonite was greatly improved. Over the sample of La/Zr/MMT, the T 98 of acetone was obtained at 350 , while it needs 400 ℃ over the pure montmorillonite. ℃ After 0.1% Pd was supported on the sample of La/Zr/MMT, the T 98 decreased from 350 to 280 ℃, indicating the montmorillonite is a promising material for the control of some types of the volatile organic compounds such as acetone.

show abstract

Interfacial properties of ZrO2 supported precious metal catalysts: A density functional study

Cited by 31 publications

References 27 publications

DFT+U study on the oxygen adsorption and dissociation on CeO2-supported platinum cluster

DFT+U study on the oxygen adsorption and dissociation on CeO2-supported platinum cluster

Size-selected Pt Nanoparticles Synthesized via Micelle Encapsulation: Effect of Pretreatment and Oxidation State on the Activity for Methanol Decomposition and Oxidation

Synthesis and Characterization of New Material‐‐La/Zr/MMT Employed in Acetone Oxidation

Contact Info

Product

Resources

About