CO2 Hydrogenation to Olefin-Rich Hydrocarbons Over Fe-Cu Bimetallic Catalysts: An Investigation of Fe-Cu Interaction and Surface Species

Previously, we reported a strong Fe-Cu synergy in CO2 hydrogenation to olefin-rich C2+ hydrocarbons over the γ-Al2O3 supported bimetallic Fe-Cu catalysts. In this work, we aimed to clarify such a synergy by investigating the catalyst structure, Fe-Cu interaction, and catalyst surface properties through a series of characterizations. H2-TPR results showed that the addition of Cu made both Fe and Cu easier to reduce via the strong interaction between Fe and Cu. It was further confirmed by X-ray absorption spectroscopy (XAS) and TEM, which showed the presence of metallic Fe and Fe-Cu alloy phases in the reduced Fe-Cu(0.17) catalyst induced by Cu addition. By correlating TPD results with the reaction performance, we found that the addition of Cu enhanced both the moderately and strongly adsorbed H2 and CO2 species, consequently enhanced CO2 conversion and C2+ selectivity. Adding K increased the adsorbed-CO2/adsorbed-H2 ratio by greatly enhancing the moderately and strongly adsorbed CO2 and slightly suppressing the moderately and strongly adsorbed H2, resulting in a significantly increased O/P ratio in the produced hydrocarbons. The product distribution analysis and in situ DRIFTS suggested that CO2 hydrogenation over the Fe-Cu catalyst involved both an indirect route with CO as the primary product and a direct route to higher hydrocarbons.

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Pd nanoparticle growth monitored by DRIFT spectroscopy of adsorbed CO

The Analyst ◽

10.1039/d0an01303j ◽

2020 ◽

Vol 145 (23) ◽

pp. 7534-7540

Author(s):

Andrei Tereshchenko ◽

Alexander Guda ◽

Vladimir Polyakov ◽

Yury Rusalev ◽

Vera Butova ◽

...

Keyword(s):

Metal Nanoparticles ◽

Absorption Spectroscopy ◽

Drift Spectroscopy ◽

X Ray ◽

Pd Nanoparticle ◽

Nanoparticle Growth ◽

Adsorbed Co ◽

X Ray Absorption

Synchrotron-based X-ray absorption spectroscopy and scattering are known in situ probes of metal nanoparticles (NPs).

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The Effects of Catalysts on Pyrolysis Products of Enzymolyzed Straw Lignin

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.345 ◽

2013 ◽

Vol 295-298 ◽

pp. 345-350

Author(s):

Tehani A.E. Yones ◽

Hai Bin Zhu ◽

Yin Xuan Fu ◽

Yong Mei Chen ◽

Ping Yu Wan

Keyword(s):

Small Molecule ◽

Aromatic Hydrocarbons ◽

Aromatic Compounds ◽

Catalytic Pyrolysis ◽

Product Distribution ◽

Immersion Method ◽

Pyrolysis Products ◽

Pyrolysis Reaction ◽

Cu Catalyst ◽

Cu Catalysts

Lignin is depolymerized to small molecule aromatic compounds, which is regarded as one of the effective ways to achieve utilization of lignin resource. In this study, Al and Cu catalysts were loaded onto enzymolyzed straw lignin by the immersion method, and the product distribution of the catalytic pyrolysis of lignin was studied by GC-MS after being extracted by solvents. Results show that both Al and Cu catalysts can promote the lignin pyrolysis reaction. Based on the comparison of the product distribution without catalyst, Al catalyst is benefit to the formation of aromatic hydrocarbons, alcohols and phenols, while Cu catalyst contribute to the formation of hydrocarbons, alcohols and ketones.

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Morphology and mechanism of highly selective Cu(II) oxide nanosheet catalysts for carbon dioxide electroreduction

Nature Communications ◽

10.1038/s41467-021-20961-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xingli Wang ◽

Katharina Klingan ◽

Malte Klingenhof ◽

Tim Möller ◽

Jorge Ferreira de Araújo ◽

...

Keyword(s):

Carbon Dioxide ◽

Gas Diffusion ◽

Reduction Reaction ◽

Flow Conditions ◽

Differential Electrochemical Mass Spectrometry ◽

Transmission Electron ◽

Cu Catalysts ◽

Shape Controlled ◽

X Ray Absorption

AbstractCu oxides catalyze the electrochemical carbon dioxide reduction reaction (CO2RR) to hydrocarbons and oxygenates with favorable selectivity. Among them, the shape-controlled Cu oxide cubes have been most widely studied. In contrast, we report on novel 2-dimensional (2D) Cu(II) oxide nanosheet (CuO NS) catalysts with high C2+ products, selectivities (> 400 mA cm−2) in gas diffusion electrodes (GDE) at industrially relevant currents and neutral pH. Under applied bias, the (001)-orientated CuO NS slowly evolve into highly branched, metallic Cu0 dendrites that appear as a general dominant morphology under electrolyte flow conditions, as attested by operando X-ray absorption spectroscopy and in situ electrochemical transmission electron microscopy (TEM). Millisecond-resolved differential electrochemical mass spectrometry (DEMS) track a previously unavailable set of product onset potentials. While the close mechanistic relation between CO and C2H4 was thereby confirmed, the DEMS data help uncover an unexpected mechanistic link between CH4 and ethanol. We demonstrate evidence that adsorbed methyl species, *CH3, serve as common intermediates of both CH3H and CH3CH2OH and possibly of other CH3-R products via a previously overlooked pathway at (110) steps adjacent to (100) terraces at larger overpotentials. Our mechanistic conclusions challenge and refine our current mechanistic understanding of the CO2 electrolysis on Cu catalysts.

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Structural change of Ni–Cu alloy nanowires with temperature studied by in situ X-ray absorption fine structure technique

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2010.01.055 ◽

2010 ◽

Vol 121 (1-2) ◽

pp. 390-394 ◽

Cited By ~ 6

Author(s):

Guang Mo ◽

Weidong Cheng ◽

Quan Cai ◽

Wei Wang ◽

Kunhao Zhang ◽

...

Keyword(s):

Fine Structure ◽

Structural Change ◽

X Ray ◽

Absorption Fine ◽

Cu Alloy ◽

Alloy Nanowires ◽

X Ray Absorption

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Influence of ion-milling on the T2 phase in Al-2.5%Li-2.5%Cu alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153415 ◽

1989 ◽

Vol 47 ◽

pp. 288-289

Author(s):

J. R. Reed ◽

D. J. Michel ◽

P. R. Howell

Keyword(s):

Thin Foil ◽

Icosahedral Symmetry ◽

Ion Milling ◽

Cu Alloy ◽

Thin Foils ◽

Heat Treated ◽

Aluminum Solid Solution ◽

In Situ Heating ◽

The Stability

The Al6Li3Cu (T2) phase, which exhibits five-fold or icosahedral symmetry, forms through solid state precipitation in dilute Al-Li-Cu alloys. Recent studies have reported that the T2 phase transforms either during TEM examination of thin foils or following ion-milling of thin foil specimens. Related studies have shown that T2 phase transforms to a microcrystalline array of the TB phase and a dilute aluminum solid solution during in-situ heating in the TEM. The purpose of this paper is to report results from an investigation of the influence of ion-milling on the stability of the T2 phase in dilute Al-Li-Cu alloy.The 3-mm diameter TEM disc specimens were prepared from a specially melted Al-2.5%Li-2.5%Cu alloy produced by conventional procedures. The TEM specimens were solution heat treated 1 h at 550°C and aged 1000 h at 190°C in air to develop the microstructure. The disc specimens were electropolished to achieve electron transparency using a 20:80 (vol. percent) nitric acid: methanol solution at -60°C.

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In Situ X-Ray Absorption Studies of the Electrochemical Reduction of Hydroxocobalamin

Journal de Physique IV (Proceedings) ◽

10.1051/jp4/1997116 ◽

1997 ◽

Vol 7 (C2) ◽

pp. C2-619-C2-620 ◽

Cited By ~ 1

Author(s):

M. Giorgett ◽

I. Ascone ◽

M. Berrettoni ◽

S. Zamponi ◽

R. Marassi

Keyword(s):

Electrochemical Reduction ◽

X Ray ◽

Absorption Studies ◽

X Ray Absorption

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Application of In Situ X-ray Absorption Spectroscopy to Study Dilute Chromium Ions in a Molten Chloride Salt

10.26434/chemrxiv.9959807 ◽

2019 ◽

Author(s):

Jisue Moon ◽

Carter Abney ◽

Dmitriy Dolzhnikov ◽

James M. Kurley ◽

Kevin A. Beyer ◽

...

Keyword(s):

Absorption Spectroscopy ◽

Local Structure ◽

Chloride Salt ◽

X Ray ◽

Molten Chloride ◽

Stable Species ◽

Higher Temperature ◽

Cr Concentration ◽

X Ray Absorption

The local structure of dilute CrCl3 in a molten MgCl2:KCl salt was investigated by in situ x-ray absorption spectroscopy (XAS) at temperatures from room temperature to 800oC. This constitutes the first experiment where dilute Cr speciation is explored in a molten chloride salt, ostensibly due to the compounding challenges arising from a low Cr concentration in a matrix of heavy absorbers at extreme temperatures. CrCl3 was confirmed to be the stable species between 200 and 500oC, while mobility of metal ions at higher temperature (>700oC) prevented confirmation of the local structure.

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Kinetic analysis of Ag particle redispersion into ZSM-5 in the presence of coke using in situ XAFS

Catalysis Science & Technology ◽

10.1039/d0cy01989e ◽

2021 ◽

Author(s):

Kazumasa Murata ◽

Junya Ohyama ◽

Atsushi Satsuma

Keyword(s):

Fine Structure ◽

Kinetic Analysis ◽

X Ray ◽

Xafs Spectroscopy ◽

Absorption Fine ◽

Ag Particles ◽

In Situ Xafs ◽

Ag Particle ◽

X Ray Absorption

In the present study, the redispersion behavior of Ag particles on ZSM-5 in the presence of coke was observed using in situ X-ray absorption fine structure (XAFS) spectroscopy.

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