CO2 Reduction to Propanol by Copper Foams: A Pre- and Post-Catalysis Study

The utilization of carbon dioxide is a major incentive for the growing field of carbon capture. Carbon dioxide could be an abundant building block to generate higher value products. Herein, we describe the use of porous copper electrodes to catalyze the reduction of carbon dioxide into higher value products such as ethylene, ethanol and, notably, propanol. For n-propanol production, faradaic efficiencies reach 4.93% at -0.83 V vs RHE, with a geometric partial current density of -1.85 mA/cm2. We have documented the performance of the catalyst in both pristine and urea-modified foams pre- and post-electrolysis. Before electrolysis, the copper electrode consisted of a mixture of cuboctahedra and dendrites. After 35-minute electrolysis, the cuboctahedra and dendrites have undergone structural rearrangement. Changes in the interaction of urea with the catalyst surface have also been observed. These transformations were characterized ex-situ using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. We found that alterations in the morphology, crystallinity, and surface composition of the catalyst led to the deactivation of the copper foams.

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Investigation into the Re-Arrangement of Copper Foams Pre- and Post-CO2 Electrocatalysis

Chemistry ◽

10.3390/chemistry3030048 ◽

2021 ◽

Vol 3 (3) ◽

pp. 687-703

Author(s):

Jennifer A. Rudd ◽

Sandra Hernandez-Aldave ◽

Ewa Kazimierska ◽

Louise B. Hamdy ◽

Odin J. E. Bain ◽

...

Keyword(s):

Crystal Structure ◽

Carbon Dioxide ◽

Carbon Capture ◽

Surface Composition ◽

Structural Rearrangement ◽

Copper Electrode ◽

Copper Electrodes ◽

Porous Copper ◽

Chemical Products ◽

Co2 Electrolysis

The utilization of carbon dioxide is a major incentive for the growing field of carbon capture. Carbon dioxide could be an abundant building block to generate higher-value chemical products. Herein, we fabricated a porous copper electrode capable of catalyzing the reduction of carbon dioxide into higher-value products, such as ethylene, ethanol and propanol. We investigated the formation of the foams under different conditions, not only analyzing their morphological and crystal structure, but also documenting their performance as a catalyst. In particular, we studied the response of the foams to CO2 electrolysis, including the effect of urea as a potential additive to enhance CO2 catalysis. Before electrolysis, the pristine and urea-modified foam copper electrodes consisted of a mixture of cuboctahedra and dendrites. After 35 min of electrolysis, the cuboctahedra and dendrites underwent structural rearrangement affecting catalysis performance. We found that alterations in the morphology, crystallinity and surface composition of the catalyst were conducive to the deactivation of the copper foams.

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Impact of water vapour and carbon dioxide on surface composition of C3A polymorphs studied by X-ray photoelectron spectroscopy

Cement and Concrete Research ◽

10.1016/j.cemconres.2015.02.026 ◽

2015 ◽

Vol 73 ◽

pp. 36-41 ◽

Cited By ~ 10

Author(s):

E. Dubina ◽

J. Plank ◽

L. Black

Keyword(s):

Carbon Dioxide ◽

Water Vapour ◽

Photoelectron Spectroscopy ◽

Surface Composition ◽

X Ray

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Effect of Surface Treatment on the Mechanical Performance of PPTA-Pulp Reinforced Rubber Composites in Supercritical Carbon Dioxide Fluid

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.2231 ◽

2017 ◽

Vol 898 ◽

pp. 2231-2238

Author(s):

Ming Lin Qin ◽

Jing Liu ◽

Ke Qing Han ◽

Fan Yu ◽

Cui Qing Teng ◽

...

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Surface Treatment ◽

Photoelectron Spectroscopy ◽

Mechanical Performance ◽

Surface Composition ◽

Rubber Matrix ◽

X Ray Diffraction ◽

X Ray ◽

Supercritical Carbon

A facile surface modification method for PPTA-pulp was developed to improve the adhesion to rubber matrix. Tensile strength tests and SEM were used to evaluate the adhesion of PPTA-pulp with rubber matrix, and the results indicated that surface treatment of PPTA pulp in supercritical carbon dioxide fluid was an efficient method to increase interfacial adhesion between PPTA-pulp and rubber matrix. Attenuated Toyal reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to investigate the surface structure and composition of untreated and treated PPTA-pulp in supercritical carbon dioxide fluid. The results indicated that the interaction of macromolecules, the crystal structure and the surface composition of PPTA-pulp changed during supercritical carbon dioxide fluid, particularly for the surface morphology and composition.

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Galvanic Replacement of Electrochemically Restructured Copper Electrodes with Gold and Its Electrocatalytic Activity for Nitrate Ion Reduction

Nanomaterials ◽

10.3390/nano8100756 ◽

2018 ◽

Vol 8 (10) ◽

pp. 756 ◽

Cited By ~ 5

Author(s):

Ali Balkis ◽

Jessica Crawford ◽

Anthony O’Mullane

Keyword(s):

Photoelectron Spectroscopy ◽

Electrochemical Techniques ◽

Cost Effective ◽

Copper Electrode ◽

Galvanic Replacement ◽

Metal Oxide Surfaces ◽

X Ray ◽

Copper Electrodes ◽

Metal Metal ◽

Increased Activity

The electrochemical formation of nanostructured materials is a cost effective route to creating substrates that can be employed in a variety of applications. In this work the surface of a copper electrode was electrochemically restructured in an alkaline solution containing ethanol as an additive to modify the surface morphology, and generate a Cu/Cu2O surface, which is known to be active for the electrocatalytic reduction of environmentally harmful nitrate ions. To increase the activity of the nanostructured surface it was decorated with gold prisms through a facile galvanic replacement approach to create an active Cu/Cu2O/Au layer. The surface was characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, as well as electrochemical techniques. It was found that the presence of recalcitrant oxides, and Au was beneficial for the increased activity compared to unmodified copper and undecorated restructured copper and was consistent with the incipient hydrous oxide adatom mediator model of electrocatalysis. This approach to generating nanostructured metal/metal oxide surfaces that can be galvanically replaced to create these types of composites may have other applications in the area of electrocatalysis.

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Electrochemical study on nickel aluminum layered double hydroxides as high-performance electrode material for lithium-ion batteries based on sodium alginate binder

Journal of Solid State Electrochemistry ◽

10.1007/s10008-021-05011-y ◽

2021 ◽

Author(s):

Xinyue Li ◽

Marco Fortunato ◽

Anna Maria Cardinale ◽

Angelina Sarapulova ◽

Christian Njel ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Electrode Material ◽

Photoelectron Spectroscopy ◽

Negative Electrode ◽

Lithium Ion ◽

Electrochemical Study ◽

Ex Situ ◽

Potential Range ◽

X Ray ◽

Storage Mechanism

AbstractNickel aluminum layered double hydroxide (NiAl LDH) with nitrate in its interlayer is investigated as a negative electrode material for lithium-ion batteries (LIBs). The effect of the potential range (i.e., 0.01–3.0 V and 0.4–3.0 V vs. Li+/Li) and of the binder on the performance of the material is investigated in 1 M LiPF6 in EC/DMC vs. Li. The NiAl LDH electrode based on sodium alginate (SA) binder shows a high initial discharge specific capacity of 2586 mAh g−1 at 0.05 A g−1 and good stability in the potential range of 0.01–3.0 V vs. Li+/Li, which is better than what obtained with a polyvinylidene difluoride (PVDF)-based electrode. The NiAl LDH electrode with SA binder shows, after 400 cycles at 0.5 A g−1, a cycling retention of 42.2% with a capacity of 697 mAh g−1 and at a high current density of 1.0 A g−1 shows a retention of 27.6% with a capacity of 388 mAh g−1 over 1400 cycles. In the same conditions, the PVDF-based electrode retains only 15.6% with a capacity of 182 mAh g−1 and 8.5% with a capacity of 121 mAh g−1, respectively. Ex situ X-ray photoelectron spectroscopy (XPS) and ex situ X-ray absorption spectroscopy (XAS) reveal a conversion reaction mechanism during Li+ insertion into the NiAl LDH material. X-ray diffraction (XRD) and XPS have been combined with the electrochemical study to understand the effect of different cutoff potentials on the Li-ion storage mechanism. Graphical abstract The as-prepared NiAl-NO3−-LDH with the rhombohedral R-3 m space group is investigated as a negative electrode material for lithium-ion batteries (LIBs). The effect of the potential range (i.e., 0.01–3.0 V and 0.4–3.0 V vs. Li+/Li) and of the binder on the material’s performance is investigated in 1 M LiPF6 in EC/DMC vs. Li. Ex situ X-ray photoelectron spectroscopy (XPS) and ex situ X-ray absorption spectroscopy (XAS) reveal a conversion reaction mechanism during Li+ insertion into the NiAl LDH material. X-ray diffraction (XRD) and XPS have been combined with the electrochemical study to understand the effect of different cutoff potentials on the Li-ion storage mechanism. This work highlights the possibility of the direct application of NiAl LDH materials as negative electrodes for LIBs.

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A Highly Sensitive Room Temperature CO2 Gas Sensor Based on SnO2-rGO Hybrid Composite

Materials ◽

10.3390/ma14030522 ◽

2021 ◽

Vol 14 (3) ◽

pp. 522

Author(s):

Zhi Yan Lee ◽

Huzein Fahmi bin Hawari ◽

Gunawan Witjaksono bin Djaswadi ◽

Kamarulzaman Kamarudin

Keyword(s):

Electron Microscopy ◽

Carbon Dioxide ◽

Gas Sensor ◽

Photoelectron Spectroscopy ◽

Hybrid Composite ◽

Room Temperature ◽

Co2 Gas ◽

X Ray ◽

Wide Range ◽

Co2 Gas Sensor

A tin oxide (SnO2) and reduced graphene oxide (rGO) hybrid composite gas sensor for high-performance carbon dioxide (CO2) gas detection at room temperature was studied. Since it can be used independently from a heater, it emerges as a promising candidate for reducing the complexity of device circuitry, packaging size, and fabrication cost; furthermore, it favors integration into portable devices with a low energy density battery. In this study, SnO2-rGO was prepared via an in-situ chemical reduction route. Dedicated material characterization techniques including field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) were conducted. The gas sensor based on the synthesized hybrid composite was successfully tested over a wide range of carbon dioxide concentrations where it exhibited excellent response magnitudes, good linearity, and low detection limit. The synergistic effect can explain the obtained hybrid gas sensor’s prominent sensing properties between SnO2 and rGO that provide excellent charge transport capability and an abundance of sensing sites.

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Dual Light- and pH-Responsive Composite of Polyazo-Derivative Grafted Cellulose Nanocrystals

Materials ◽

10.3390/ma11091725 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1725 ◽

Cited By ~ 5

Author(s):

Xiaohong Liu ◽

Ming Li ◽

Xuemei Zheng ◽

Elias Retulainen ◽

Shiyu Fu

Keyword(s):

Cellulose Nanocrystals ◽

Photoelectron Spectroscopy ◽

Surface Composition ◽

X Ray Diffraction ◽

Responsive Materials ◽

X Ray ◽

Ph Response ◽

Transmission Electron ◽

Ft Ir ◽

Hexyl Methacrylate

As a type of functional group, azo-derivatives are commonly used to synthesize responsive materials. Cellulose nanocrystals (CNCs), prepared by acid hydrolysis of cotton, were dewatered and reacted with 2-bromoisobuturyl bromide to form a macro-initiator, which grafted 6-[4-(4-methoxyphenyl-azo) phenoxy] hexyl methacrylate (MMAZO) via atom transfer radical polymerization. The successful grafting was supported by Fourier transform infrared spectroscopy (FT-IR) and Solid magnetic resonance carbon spectrum (MAS 13C-NMR). The morphology and surface composition of the poly{6-[4-(4-methoxyphenylazo) phenoxy] hexyl methacrylate} (PMMAZO)-grafted CNCs were confirmed with Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The grafting rate on the macro-initiator of CNCs was over 870%, and the polydispersities of branched polymers were narrow. The crystal structure of CNCs did not change after grafting, as determined by X-ray diffraction (XRD). The polymer PMMAZO improved the thermal stability of cellulose nanocrystals, as shown by thermogravimetry analysis (TGA). Then the PMMAZO-grafted CNCs were mixed with polyurethane and casted to form a composite film. The film showed a significant light and pH response, which may be suitable for visual acid-alkali measurement and reversible optical storage.

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