Effects of confinement in hybrid diamine-Rh complex-carbon catalysts used for hydrogenation reactions

Lemus-Yegres, L.J.; Román-Martı́nez, M.C.; Such-Basáñez, I.; Lecea, C. Salinas-Martı́nez de

doi:10.1016/j.micromeso.2007.05.005

Cited by 26 publications

(29 citation statements)

References 28 publications

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“…Research has shown that metal particles (i.e., Ru, Co, and Fe) encapsulated inside CNTs exhibit superior catalytic performance compared with those loaded outside CNTs in hydrogenation [16], oxygen reduction [17], Fischer-Tropsch synthesis [18,19], and polymerization [20]. This superior catalytic performance can be attributed to the unique "confinement effect" of CNTs [21][22][23][24].…”

Section: Resultsmentioning

confidence: 99%

Hydrogenation of Phenol over Pt/CNTs: The Effects of Pt Loading and Reaction Solvents

Cao

Zhu

et al. 2017

Catalysts

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Carbon nanotubes (CNTs)-supported Pt nanoparticles were prepared with selective deposition of Pt nanoparticles inside and outside CNTs (Pt-in/CNTs and Pt-out/CNTs). The effects of Pt loading and reaction solvents on phenol hydrogenation were investigated. The Pt nanoparticles in Pt-in/CNTs versus Pt-out/CNTs are smaller and better dispersed. The catalytic activity and reuse stability toward phenol hydrogenation both improved markedly. The dichloromethane-water mixture as the reaction solvent, compared with either pure medium, decreased the catalytic activity toward phenol hydrogenation and selectivity of cyclohexanone over Pt-in/CNTs, but significantly improved the catalytic activity toward phenol hydrogenation and selectivity of cyclohexanone over Pt-out/CNTs.

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Section: Resultsmentioning

confidence: 99%

Hydrogenation of Phenol over Pt/CNTs: The Effects of Pt Loading and Reaction Solvents

Cao

Zhu

et al. 2017

Catalysts

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“…The calculated F values give an indication of the location of the Rh species [24]. As a larger value of F corresponds to a more external location, the data indicate that the support properties M a n u s c r i p t 12 largely affect this aspect; the distribution of the Rh species is more homogeneous in carbon nanotubes than in carbon xerogels.…”

Section: Page 13 Of 24mentioning

confidence: 89%

“…The study of the surface chemistry was carried out by Temperature Programmed The rhodium content in the catalysts was determined after metal extraction and analysis of the solution by ICP-OES, using the methodology described in the literature [24]. The catalysts were also characterized by XPS employing a VG-Microtech Multilab 3000 spectrometer.…”

Section: Characterizationmentioning

confidence: 99%

Non-covalent immobilization of RhDuphos on carbon nanotubes and carbon xerogels

Gheorghiu

Lecea

Román-Martı́nez

2014

Applied Catalysis A: General

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A c c e p t e d M a n u s c r i p t Research highlights The chiral catalyst RhDuphos has been anchored on carbon nanotubes and xerogels.  Non covalent anchoring strategies were used: electrostatic and - interactions.  Supports have been chemically modified to promote desired interactions.  RhDuphos on an oxidized carbon xerogel is active, enantioselective and reusable. The immobilization of the chiral complex RhDuphos, by electrostatic or π-π (adsorption) interactions, on carbon nanotubes and carbon xerogels is investigated. To promote such interactions, the supports were either oxidized or heat treated to create carboxylic type surface groups or an apolar surface, respectively. The catalysts were tested in the hydrogenation of methyl 2-acetamidoacrylate.The prepared hybrid catalysts are less active than the homogeneous RhDuphos, but most of them show a high enantioselectivity and the one prepared with the oxidized carbon xerogel is also reusable, being able to give a high substrate conversion, keeping as well a high enantioselectivity. The anchorage by electrostatic interactions is more interesting than the anchorage by - interactions, as the π-π adsorption method produces a modification of the metal complex structure leading to an active hybrid catalyst but without enantioselectivity.The creation of carboxylic groups on the support surface has led to some hindering of the complex leaching.

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“…As previously reported [26][27][28], the anchoring on the support is assumed to occur through a covalent siloxane-type bond created by reaction of methoxy functions with surface -OH type groups. It has been found that catalysts prepared in this way on different carbon materials are, in general, more active than the Rh(NN)Si in homogeneous phase and they are reusable [26][27][28]. Therefore, it was decided to extend the study to two structured carbon-based supports such as the CNF-monolith described above and a granular carbon xerogel.…”

Section: Introductionmentioning

confidence: 88%

Structured carbons as supports for hydrogenation hybrid catalysts prepared by the immobilization of a Rh diamine complex

Gheorghiu

García‐Bordejé

Job

et al. 2016

Chemical Engineering Journal

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Effects of confinement in hybrid diamine-Rh complex-carbon catalysts used for hydrogenation reactions

Cited by 26 publications

References 28 publications

Hydrogenation of Phenol over Pt/CNTs: The Effects of Pt Loading and Reaction Solvents

Hydrogenation of Phenol over Pt/CNTs: The Effects of Pt Loading and Reaction Solvents

Non-covalent immobilization of RhDuphos on carbon nanotubes and carbon xerogels

Structured carbons as supports for hydrogenation hybrid catalysts prepared by the immobilization of a Rh diamine complex

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