[AuAg26(SR)18S]− Nanocluster: Open Shell Structure and High Faradaic Efficiency in Electrochemical Reduction of CO2 to CO

Herein, we present fabrication of graphene oxide supported Cu/CuxO nano-electrodeposits which efficiently and selectively can electroreduce CO2 into ethylene with a faradaic efficiency of 34% and conversion rate of 194 mmol g−1 h−1 at −0.985 V vs. RHE.

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Low-Overpotential Electrochemical Reduction of CO2 to Formic Acid on Surface-Modified Doped Tin Oxide Pellets

10.1149/osf.io/2u8ba ◽

2019 ◽

Author(s):

Emmanuel Abdul ◽

Jason Pitts ◽

Deepak Rajput ◽

Shankar Rananavare

Keyword(s):

Formic Acid ◽

Electrochemical Reduction ◽

Current Density ◽

Tin Oxide ◽

Aqueous Media ◽

Oxide Nanoparticles ◽

Faradaic Efficiency ◽

Electrode Potentials ◽

Tin Oxide Nanoparticles ◽

Reduction Of Co2

Gas sensors fabricated with antimony doped tin oxide (ATO) nanomaterials exhibit remarkable sensitivity for detecting oxidizing and reducing gases. This study highlights the enhanced selectivity and stability of the porous ATO nanomaterial electrode made for electrochemical reduction of CO2 in aqueous media. During electrochemical reduction, these electrodes prepared from compressed powders tend to crumble within a few hours in aqueous media. To overcome this electrode disintegration effect, we modified the surface of the doped tin-Oxide nanoparticles with Nafion and a dipodal silane (1,2-Bis(triethoxysilyl)ethane). The electrode characterization studies include Cyclic Voltammetry (CV), and Electrochemical Impedance Spectroscopy (EIS). Scanning electron microscopic investigation of electrode surface morphology and roughness before and after electrochemical CO2 reduction for derivatized and underivatized electrode revealed lower surface roughness for former than the latter.The derivatized electrodes allowed CO2 electrochemical reduction at low overpotentials and high current density without any electrode crumbling over more than 24 hours of continuous operation. Formate/formic acid and methanol were the major products of reduction at electrode potentials ranging from -0.4 to -1.0V vs. RHE in the CO2 saturated 0.1M KHCO3 electrolyte. Higher current density and Faradaic Efficiency of formic acid was observed when compared to planar tin electrode materials and tin oxide nanoparticles deposited on FTO glass.

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Arc Plasma Deposited Copper and Gold Nanoparticles on FTO Substrate for Electrochemical Reduction of CO2

Advances in Nanoscience and Nanotechnology ◽

10.33140/ann.03.01.03 ◽

2019 ◽

Vol 3 (1) ◽

Keyword(s):

Gold Nanoparticles ◽

Formic Acid ◽

Electrochemical Reduction ◽

High Efficiency ◽

Plasma Deposition ◽

Arc Plasma ◽

Faradaic Efficiency ◽

Electro Deposition ◽

Electro Catalysis ◽

Reduction Of Co2

A composite of copper and gold nanoparticles was deposited using arc plasma deposition on the conductive FTO substrate for the electrochemical reduction of CO2 . The use of arc plasma deposition system allows the nanoparticles to be implanted onto the substrate as opposed to the commonly used methods of vacuum deposition or electro deposition. This unique structure reduced the CO2 to produce formic acid with up to 60% faradaic efficiency. Copper and gold nanoparticles have never previously been reported to produce formic acid with such high efficiency, suggesting that the co-deposition technique of implanted nanoparticles can provide an interesting future avenue in the field of electrochemical reduction of CO2 . The surface analysis of the electrodes is presented here along with potential dependent faradaic efficiency of the electro catalysis.

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Electrochemical Reduction of CO2 to Formate on Easily Prepared Carbon-Supported Bi Nanoparticles

Molecules ◽

10.3390/molecules24112032 ◽

2019 ◽

Vol 24 (11) ◽

pp. 2032 ◽

Cited By ~ 12

Author(s):

Beatriz Ávila-Bolívar ◽

Leticia García-Cruz ◽

Vicente Montiel ◽

José Solla-Gullón

Keyword(s):

Electron Microscopy ◽

Electrochemical Reduction ◽

Carbon Paper ◽

Faradaic Efficiency ◽

X Ray ◽

Bismuth Nanoparticles ◽

Electrode Potentials ◽

Co2 Electroreduction ◽

Reduction Of Co2 ◽

Bi Nanoparticles

Herein, the electrochemical reduction of CO2 to formate on carbon-supported bismuth nanoparticles is reported. Carbon-supported Bi nanoparticles (about 10 nm in size) were synthesized using a simple, fast and scalable approach performed under room conditions. The so-prepared Bi electrocatalyst was characterized by different physicochemical techniques, including transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction and subsequently air-brushed on a carbon paper to prepare electrodes. These electrodes were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy and also by cyclic voltammetry. Finally, CO2 electroreduction electrolyses were performed at different electrode potentials for 3 h. At the optimal electrode potential (−1.6 V vs AgCl/Ag), the concentration of formate was about 77 mM with a faradaic efficiency of 93 ± 2.5%. A 100% faradaic efficiency was found at a lower potential (−1.5 V vs AgCl/Ag) with a formate concentration of about 55 mM. In terms of stability, we observed that after about 70 h (in 3 h electrolysis experiments at different potentials), the electrode deactivates due to the gradual loss of metal as shown by SEM/EDX analyses of the deactivated electrodes.

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Highly ordered mesoporous carbon/iron porphyrin nanoreactor for the electrochemical reduction of CO2

Journal of Materials Chemistry A ◽

10.1039/d0ta04641h ◽

2020 ◽

Vol 8 (30) ◽

pp. 14966-14974 ◽

Cited By ~ 1

Author(s):

Jaecheol Choi ◽

Jeonghun Kim ◽

Pawel Wagner ◽

Jongbeom Na ◽

Gordon G. Wallace ◽

...

Keyword(s):

Electrochemical Reduction ◽

Surface Area ◽

Mesoporous Carbon ◽

Ordered Mesoporous Carbon ◽

Iron Porphyrin ◽

Faradaic Efficiency ◽

Ordered Mesoporous ◽

Conductive Substrate ◽

Carbon Iron ◽

Reduction Of Co2

A highly ordered mesoporous carbon having a large surface area is utilized as a conductive substrate to immobilize iron porphyrin catalysts for electrochemical CO2 reduction, resulting in the selective conversion of aqueous CO2 into CO with 92.1% faradaic efficiency.

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Optimizing Temperature Treatment of Copper Hollow Fibers for the Electrochemical Reduction of CO2 to CO

Catalysts ◽

10.3390/catal11050571 ◽

2021 ◽

Vol 11 (5) ◽

pp. 571

Author(s):

Khalid Khazzal Hummadi ◽

Anne Sustronk ◽

Recep Kas ◽

Nieck Benes ◽

Guido Mul

Keyword(s):

Electrochemical Reduction ◽

Subsequent Treatment ◽

Treatment Temperature ◽

Hollow Fibers ◽

Hydrogen Treatment ◽

Gravimetric Analysis ◽

Hydrogen Electrode ◽

Faradaic Efficiency ◽

Copper Particles ◽

Reduction Of Co2

Copper hollow fibers were prepared via dry-wet spinning of a polymer solution of N-methylpyrrolidone, Polyetherimide, Polyvinyl Pyrolidone, and copper particles of sizes in the range of 1–2 µm. To remove template molecules and to sinter the copper particles, the time of calcination was varied in a range of 1–4 h at 600 °C. This calcination temperature was determined based on Thermal Gravimetric Analysis (TGA), showing completion of hydrocarbon removal at this temperature. Furthermore, the temperature of the subsequent treatment of the fibers in a flow of 4% H2 (in Ar) was varied in the range of 200 °C to 400 °C, at a fixed time of 1 h. Temperature programmed reduction experiments (TPR) were used to analyze the hydrogen treatment. The Faradaic Efficiency (FE) towards CO in electrochemical reduction of CO2 was determined at −0.45 V vs. RHE (Reversible Hydrogen Electrode), using a 0.3 M KHCO3 electrolyte. A calcination time of 3 h at 600 °C and a hydrogen treatment temperature of 280 °C were found to induce the highest FE to CO of 73% at these constant electrochemical conditions. Optimizing oxidation properties is discussed to likely affect porosity, favoring the CO2 gas distribution over the length of the fiber, and hence the CO2 reduction efficiency. Treatment in H2 in the range of 250 to 300 °C is proposed to affect the content of residual (subsurface) oxygen in Cu, which leads to favorable properties on the nanoscale.

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CO2-Induced Fibrous Zn Catalyst Promotes Electrochemical Reduction of CO2 to CO

Catalysts ◽

10.3390/catal11040477 ◽

2021 ◽

Vol 11 (4) ◽

pp. 477

Author(s):

Mengquan Guo ◽

Xiangxiang Li ◽

Yuxin Huang ◽

Linfa Li ◽

Jixiao Li ◽

...

Keyword(s):

Electrochemical Reduction ◽

Active Surface ◽

Active Surface Area ◽

Atmospheric Conditions ◽

X Ray Diffraction ◽

Faradaic Efficiency ◽

Highly Active ◽

Fibrous Morphology ◽

Reduction Of Co2 ◽

Area X

The electrochemical reduction of CO2 is a promising strategy to achieve efficient conversion and utilization. In this paper, a series of Zn catalysts were prepared by electrodeposition in different atmospheric conditions (N2, CO2, H2, CO). A fibrous Zn catalyst (Zn-CO2) exhibits high electrochemical activity and stability. The Zn-CO2 catalyst shows 73.0% faradaic efficiency of CO at −1.2 V vs. RHE and the selectivity of CO almost did not change over 6 h in −1.2 V vs. RHE. The excellent selectivity and stability is attributed to the novel fibrous morphology, which increases the electrochemical active surface area. X-ray diffraction (XRD) results show that Zn-CO2 catalyst has a higher proportion of Zn (101) crystal planes, which is considered to be conducive to the production of CO. The search further demonstrates the importance of morphology control for the preparation of highly active and stable catalysts.

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Mo–Bi Bimetallic Chalcogenide Nanoparticles Supported on CNTs for the Efficient Electrochemical Reduction of CO2 to Methanol

Coatings ◽

10.3390/coatings10121142 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1142

Author(s):

Chen Chi ◽

Donghong Duan ◽

Zhonglin Zhang ◽

Guoqiang Wei ◽

Yu Li ◽

...

Keyword(s):

Electrochemical Reduction ◽

Average Particle Size ◽

Reference Electrode ◽

Catalytic Performance ◽

Industrial Applications ◽

Saturated Calomel Reference Electrode ◽

Average Particle ◽

One Pot ◽

Faradaic Efficiency ◽

Reduction Of Co2

The electrochemical reduction of CO2 to methanol is a promising strategy, which currently suffers from the poor catalytic activity, selectivity, and stability of the electrode. Here, we report a simple one-pot hydrothermal strategy to fabricate Mo–Bi BMC@CNT nanocomposites, in which Mo–Bi bimetallic chalcogenide nanoparticles were in-situ decorated on carbon nanotubes. The Mo–Bi BMC nanoparticles with an average particle size of 12 nm were uniformly supported on the surface of CNTs without aggregation into larger clusters. The Mo–Bi BMC@CNT nanocomposites exhibited a relatively good catalytic performance for the electrochemical reduction of CO2 to methanol in a 60 wt.% 1-ethyl-3-methylimidazolium tetrafluoroborate aqueous electrolyte. Among them, the Mo–Bi BMC@CNT-15% nanocomposite showed the highest Faradaic efficiency of 81% for methanol at −0.3 V vs. a saturated calomel reference electrode (SCE) and a stable current density is 5.6 mA cm−2 after a run time of 12 h. The excellent catalytic properties are likely attributed to its nanostructure and fast electron transfer. These derive from the synergistic effect of Mo–Bi and the high conductivity of CNTs. This work opens a way to provide an efficient catalytic system for the electroreduction of CO2 to methanol in industrial applications.

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Electrochemical Reduction of CO2: Overcoming Chemical Inertness at Ambient Conditions

Electrochem ◽

10.3390/electrochem1010006 ◽

2020 ◽

Vol 1 (1) ◽

pp. 56-59

Author(s):

Ana Cristina Perez ◽

Manuel Antonio Diaz-Perez ◽

Juan Carlos Serrano-Ruiz

Keyword(s):

Electrochemical Reduction ◽

Active Sites ◽

Storage System ◽

Reduction Process ◽

Electrochemical Reactor ◽

Great Promise ◽

Ambient Conditions ◽

Faradaic Efficiency ◽

Fine Control ◽

Reduction Of Co2

Electroreduction allows for the transformation of a chemically inert molecule such as CO2 into a wide variety of useful carbon products. Unlike other approaches operating at higher temperatures, electrochemical reduction holds great promise since it achieves reduction under ambient conditions, thereby providing more control over the reaction selectivity. By controlling basic parameters such as the potential and the composition of the electrode, CO2 can be transformed into a variety of products including carbon monoxide, syngas (CO/H2), methane, and methanol. This reduction process takes place without external hydrogen, since water can be used as a source of both electrons and protons. Furthermore, this technology, when combined with renewable wind- or solar-derived electricity, has the potential to serve as a storage system for excess electricity. Despite these advantages, a number of challenges need to be overcome before reaching commercialization. New (and cheaper) electrocatalyst formulations with high faradaic selectivities are required. Impressive progress has been made on carbon-doped materials, which, in certain cases, have outperformed expensive noble metal-based materials. Research is also needed on new electrochemical reactor configurations able to overcome kinetic/mass transport limitations, which are crucial to reduce overpotentials. Fine control over the nature of the active sites and the reaction conditions is important to avoid parasitic reactions such as the hydrogen evolution reaction (HER), and therefore increases the faradaic efficiency towards the desired products.

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