Selectivity and stoichiometry of copper oxide in propylene oxidation

Wood, Bernard J.; Wise, Henry; Yolles, Robert S.

doi:10.1016/0021-9517(69)90304-2

Cited by 74 publications

(22 citation statements)

References 12 publications

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“…These injecting electrons from their excited states into the conduction band of the Cu 2 O nanobelts under daylight irradiation accelerate the production of superoxide and hydroxyl radicals, and drastically improve the reaction rates of MO photodegradation. The p-type Cu 2 O semiconductors are known to absorb a relatively large amount of oxygen as O 2 — on the surface [ 43 ], which further accelerate the reaction rates of MO degradation as well. Wholly speaking, the belt-shaped Cu 2 O nanostructures have almost four times higher photodegradation rate than NPC, and one order higher than polyhedral Cu 2 O and other Cu 2 O microcrystals [ 42 ].…”

Section: Resultsmentioning

confidence: 99%

Facile Fabrication of Cu2O Nanobelts in Ethanol on Nanoporous Cu and Their Photodegradation of Methyl Orange

et al. 2018

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Thin cupric oxide (Cu2O) nanobelts with width of few tens of nanometers to few hundreds of nanometers were fabricated in anhydrous ethanol on nanoporous copper templates that was prepared via dealloying amorphous Ti40Cu60 ribbons in hydrofluoric acid solutions at 348 K. The Cu2O octahedral particles preferentially form in the water, and nanobelts readily undergo the growth along the lengthwise and widthwise in the anhydrous ethanol. The ethanol molecules serve as stabilizing or capping reagents, and play a key role of the formation of two-dimensional Cu2O nanobelts. Cu atoms at weak sites (i.e., twin boundary) on the nanoporous Cu ligaments are ionized to form Cu2+ cations, and then react with OH− to form Cu2O and H2O. The two-dimensional growth of Cu2O nanostructure is preferred in anhydrous ethanol due to the suppression of random growth of Cu2O nanoarchitectures by ethanol. Cu2O nanobelts have superior photodegradation performance of methyl orange, three times higher than nanoporous Cu.

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Section: Resultsmentioning

confidence: 99%

Facile Fabrication of Cu2O Nanobelts in Ethanol on Nanoporous Cu and Their Photodegradation of Methyl Orange

et al. 2018

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“…While these low pressure and low temperature results for the (111) surface clearly cannot be assumed to be characteristic of real powder catalysts under reaction conditions, there are interesting parallels to another study in the literature. From studies of propene oxidation on polycrystalline Cu?0, Wood et al found that a copper rich (i.e., oxygen deficient) surface favors selective oxidation to acrolein, while an oxygen rich surface favors nonselective oxidation (14). This compositional observation suggests that the potential importance of point defects like oxygen vacancies in controlling the selectivity of Οι 2 0 catalysts cannot not be overlooked.…”

Section: Catalytic Consequences Of the Structure Sensitivitymentioning

confidence: 93%

Structure Sensitivity in Selective Oxidation of Propene over Cu₂O Surfaces

Schulz¹,

Cox²

1993

ACS Symposium Series

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Studies of the interaction of propene (CH 2 =CHCH 3 ) with Cu 2 O(111) and (100) single crystal surfaces have demonstrated that each step in the allylic oxidation to acrolein (CH 2 =CHCHO) exhibits structure-sensitivity. Oxygen vacancies (i.e., surface defects) on the nonpolar, Cu 2 O(111) surface have been found to be energetically-favorable sites for the dissociation of propene to allyl when compared to (100) and non-defective (111) surfaces. The oxygen insertion reaction requires the presence of coordinately-unsaturated surface lattice oxygen. The final reaction step is hydrogen elimination from the carbon α to oxygen in the σ-bonded allylic intermediate (identified as a surface allyloxy, CH 2 =CHCH 2 O-). The activation energy for this final reaction varies by over 7 kcal/mol depending on which Cu 2 O surface is investigated.The partial oxidation of propene (CH 2 = CHCH3) to acrolein (CH 2 = CHCHO) is a useful model for the class of allylic oxidation reactions of olefins. Several mixed oxides catalyze this reaction, but Cu 2 O is the only reported single-component oxide catalyst to exhibit significant activity and selectivity (1-3). Because of its single-component nature, single crystal Cu 2 O was chosen for investigating the structure sensitivity and site requirements for the propene selective oxidation reaction.The basic steps in the reaction pathway of propene oxidation to acrolein have been widely studied. In the rate determining step over Cu 2 O and bismuth-molybdate catalysts, a methyl hydrogen is abstracted from propene to produce a symmetric, π-allyl intermediate (4,5). The order in which the second and third steps occur is not well understood, but involves a second hydrogen abstraction and lattice oxygen insertion into the symmetric π-allyl to form an oxygen-containing σ-allyl species. Grasselli and 1

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“…In fact, the Schottky barrier were assumed to form at the Cu 2 O and 3DG interface, 3DG act as an electron acceptor and sink that reduces the recombination of photoinduced. It has been proved that the accumulate on 3DG particles while the hole oxidize the organics through the formation of * OH and * OHH radicals [13]. However, Cu 2 O is known to absorb a relatively large amount of oxygen on the surface [14].…”

Section: Adsorption and Photocatalytic Activitymentioning

confidence: 99%

3D Graphene/Cu2O Nanocomposite as a Highly Efficient Sorbent and Photocatalysis

Zhou¹,

Wu²

2017

JRST

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There-dimensional graphene (3Dg)/Cu 2 o nanocomposites are prepared using one-pot template-free solvent-thermal synthesis route with (Ch 3 Coo) 2 Cu·h 2 o as a precursor. The cube Cu 2 o nanoparticles are deposited on the spongy nanosheets of 3Dg. The adsorbent experiment reveals that the 3Dg/Cu 2 o has a adsorption rate of 83.34% which is 14 times higher than that of pure Cu 2 o. using photocatalytic degradation of methyl orange (Mo) under visible-light illumination to investigate the photocatalytic activity of 3Dg/Cu 2 o. The prepared 3Dg/Cu 2 o particles exhibited a higher photo-degradation capability than Cu 2 o. The superior activity of 3Dg/Cu 2 o for Mo decomposition can be attributed to not only its nanoporous structure and large specific surface area, but also the strong interaction between 3Dg and Cu 2 o from in-situ synthesis.

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Selectivity and stoichiometry of copper oxide in propylene oxidation

Cited by 74 publications

References 12 publications

Facile Fabrication of Cu2O Nanobelts in Ethanol on Nanoporous Cu and Their Photodegradation of Methyl Orange

Facile Fabrication of Cu2O Nanobelts in Ethanol on Nanoporous Cu and Their Photodegradation of Methyl Orange

Structure Sensitivity in Selective Oxidation of Propene over Cu₂O Surfaces

3D Graphene/Cu2O Nanocomposite as a Highly Efficient Sorbent and Photocatalysis

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Selectivity and stoichiometry of copper oxide in propylene oxidation

Cited by 74 publications

References 12 publications

Facile Fabrication of Cu2O Nanobelts in Ethanol on Nanoporous Cu and Their Photodegradation of Methyl Orange

Facile Fabrication of Cu2O Nanobelts in Ethanol on Nanoporous Cu and Their Photodegradation of Methyl Orange

Structure Sensitivity in Selective Oxidation of Propene over Cu2O Surfaces

3D Graphene/Cu2O Nanocomposite as a Highly Efficient Sorbent and Photocatalysis

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Structure Sensitivity in Selective Oxidation of Propene over Cu₂O Surfaces