AuCu nanofibers for electrosynthesis of urea from carbon dioxide and nitrite

Abstract Carbon dioxide reduction reaction (CO2RR) is a promising technology for mitigating greenhouse gas emission and achieving carbon neutrality. However, coupling CO2RR with other reactions to produce high value-added chemicals remains a challenge. In this work, we report self-assembled nanofibers composed of ultra-thin AuCu alloy nanowires possessing a Boerdijk-Coxeter structure with (111)-dominant facets for the electrosynthesis of urea by coupling CO2RR with nitrite reduction reaction (NO2−RR). The rich structural defects and AuCu bimetallic alloy composition provide a large number of highly catalytically active sites. The constructed AuCu nanofibers display excellent urea synthesis performance in the electrolyte solution containing 0.01 M KNO2 with continuous drumming of CO2, achieving a high urea yield rate of up to 3889.6 µg h− 1 mg− 1cat. and a high Faraday efficiency of 24.7% at -0.9 V. This work provides a feasible method for the rational design of self-assembled bimetallic nanofibers for electrosynthesis of urea under ambient conditions.

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Phase-selective active sites on ordered/disordered titanium dioxide enable exceptional photocatalytic ammonia synthesis

Chemical Science ◽

10.1039/d1sc03223b ◽

2021 ◽

Author(s):

Jinsun Lee ◽

Xinghui Liu ◽

Ashwani Kumar ◽

Yosep Hwang ◽

Eunji Lee ◽

...

Keyword(s):

Titanium Dioxide ◽

Active Sites ◽

Rational Design ◽

Ammonia Synthesis ◽

Reduction Reaction ◽

Band Structures ◽

Electronic Band ◽

Defect Sites ◽

Electronic Band Structures ◽

Reaction Routes

This work highlights the importance of a rational design for more energetically suitable nitrogen reduction reaction routes and mechanisms by regulating the electronic band structures with phase-selective defect sites.

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Hierarchical three-dimensional copper selenide nanocubes microelectrodes for improved carbon dioxide reduction reaction

Sustainable Energy & Fuels ◽

10.1039/d1se01458g ◽

2021 ◽

Author(s):

Rajasekaran Elakkiya ◽

Govindhan Maduraiveeran

Keyword(s):

Carbon Dioxide ◽

High Performance ◽

Three Dimensional ◽

Co2 Reduction ◽

Value Added ◽

Carbon Dioxide Reduction ◽

Reduction Reaction ◽

Earth Abundant ◽

Carbon Dioxide Co2 ◽

Co2 Reduction Reaction

Design of high-performance and Earth-abundant electrocatalysts for electrochemical carbon dioxide (CO2) reduction reaction (CO2RR) into fuels and value-added chemicals offers an emergent pathway for environment and energy sustainable concerns. Herein,...

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Heterogeneous Electrocatalysts for CO2 Reduction to Value Added Products

10.5772/intechopen.97274 ◽

2021 ◽

Author(s):

M. Amin Farkhondehfal ◽

Juqin Zeng

Keyword(s):

Fossil Fuels ◽

Greenhouse Gas Emission ◽

Global Climate ◽

Renewable Energy Sources ◽

Critical Role ◽

Co2 Reduction ◽

Value Added ◽

Reduction Reaction ◽

Added Value ◽

Global Climate Changes

The CO2 that comes from the use of fossil fuels accounts for about 65% of the global greenhouse gas emission, and it plays a critical role in global climate changes. Among the different strategies that have been considered to address the storage and reutilization of CO2, the transformation of CO2 into chemicals and fuels with a high added-value has been considered a winning approach. This transformation is able to reduce the carbon emission and induce a “fuel switching” that exploits renewable energy sources. The aim of this chapter is to categorize different heterogeneous electrocatalysts which are being used for CO2 reduction, based on the desired products of the above mentioned reactions: from formic acid and carbon monoxide to methanol and ethanol and other possible by products. Moreover, a brief description of the kinetic and mechanism of the CO2 reduction reaction) and pathways toward different products have been discussed.

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Promoting CO2 methanation via ligand-stabilized metal oxide clusters as hydrogen-donating motifs

Nature Communications ◽

10.1038/s41467-020-20004-7 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Yuhang Li ◽

Aoni Xu ◽

Yanwei Lum ◽

Xue Wang ◽

Sung-Fu Hung ◽

...

Keyword(s):

Carbon Dioxide ◽

Metal Oxide ◽

Active Sites ◽

Density Functional ◽

Copper Catalyst ◽

Value Added ◽

Adsorbed Hydrogen ◽

Co2 Methanation ◽

Faradaic Efficiency ◽

Metal Oxide Clusters

AbstractElectroreduction uses renewable energy to upgrade carbon dioxide to value-added chemicals and fuels. Renewable methane synthesized using such a route stands to be readily deployed using existing infrastructure for the distribution and utilization of natural gas. Here we design a suite of ligand-stabilized metal oxide clusters and find that these modulate carbon dioxide reduction pathways on a copper catalyst, enabling thereby a record activity for methane electroproduction. Density functional theory calculations show adsorbed hydrogen donation from clusters to copper active sites for the *CO hydrogenation pathway towards *CHO. We promote this effect via control over cluster size and composition and demonstrate the effect on metal oxides including cobalt(II), molybdenum(VI), tungsten(VI), nickel(II) and palladium(II) oxides. We report a carbon dioxide-to-methane faradaic efficiency of 60% at a partial current density to methane of 135 milliampere per square centimetre. We showcase operation over 18 h that retains a faradaic efficiency exceeding 55%.

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Rational design of a highly mesoporous Fe–N–C/Fe3C/C–S–C nanohybrid with dense active sites for superb electrocatalysis of oxygen reduction

Journal of Materials Chemistry A ◽

10.1039/d0ta06987f ◽

2020 ◽

Vol 8 (44) ◽

pp. 23436-23454

Author(s):

Ahmed Al-Shahat Eissa ◽

Nam Hoon Kim ◽

Joong Hee Lee

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Active Sites ◽

High Performance ◽

Rational Design ◽

Reduction Reaction ◽

Single Step

A high-performance and sustainable electrocatalyst for the oxygen reduction reaction is fabricated by a single-step doping/annealing strategy.

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Electro-reduction of carbon dioxide at low over-potential at a metal–organic framework decorated cathode

Nature Communications ◽

10.1038/s41467-020-19236-4 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Xinchen Kang ◽

Lili Li ◽

Alena Sheveleva ◽

Xue Han ◽

Jiangnan Li ◽

...

Keyword(s):

Carbon Dioxide ◽

Formic Acid ◽

Active Sites ◽

Metal Organic Framework ◽

Computational Modelling ◽

Structural Defects ◽

Resonance Spectroscopy ◽

Faradaic Efficiency ◽

Metal Organic ◽

Organic Framework

Abstract Electrochemical reduction of carbon dioxide is a clean and highly attractive strategy for the production of organic products. However, this is hindered severely by the high negative potential required to activate carbon dioxide. Here, we report the preparation of a copper-electrode onto which the porous metal–organic framework [Cu2(L)] [H4L = 4,4′,4″,4′′′-(1,4-phenylenebis(pyridine-4,2,6-triyl))tetrabenzoic acid] can be deposited by electro-synthesis templated by an ionic liquid. This decorated electrode shows a remarkable onset potential for reduction of carbon dioxide to formic acid at −1.45 V vs. Ag/Ag+, representing a low value for electro-reduction of carbon dioxide in an organic electrolyte. A current density of 65.8 mA·cm−2 at −1.8 V vs. Ag/Ag+ is observed with a Faradaic efficiency to formic acid of 90.5%. Electron paramagnetic resonance spectroscopy confirms that the templated electro-synthesis affords structural defects in the metal–organic framework film comprising uncoupled Cu(II) centres homogenously distributed throughout. These active sites promote catalytic performance as confirmed by computational modelling.

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CuAg nanoparticles/carbon aerogel for electrochemical CO2 reduction

New Journal of Chemistry ◽

10.1039/d1nj03540a ◽

2021 ◽

Author(s):

Wenbo Wang ◽

Runqing Lu ◽

Xin-Xin Xiao ◽

Shanhe Gong ◽

Daniel Kobina Sam ◽

...

Keyword(s):

Carbon Dioxide ◽

Greenhouse Gas ◽

Co2 Reduction ◽

Value Added ◽

Electrical Energy ◽

Carbon Aerogel ◽

Carbon Dioxide Reduction ◽

Reduction Reaction ◽

Electrochemical Co2 Reduction ◽

Value Added Products

Electrochemical carbon dioxide reduction reaction (eCO2RR) is a promising technology that uses electrical energy to catalytically reduce the greenhouse gas-CO2, which can convert CO2 into high value-added products such as...

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Regulating Fe-spin state by atomically dispersed Mn-N in Fe-N-C catalysts with high oxygen reduction activity

Nature Communications ◽

10.1038/s41467-021-21919-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Gege Yang ◽

Jiawei Zhu ◽

Pengfei Yuan ◽

Yongfeng Hu ◽

Gan Qu ◽

...

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Spin State ◽

Active Sites ◽

Rational Design ◽

Magnetic Measurements ◽

Low Cost ◽

Reduction Reaction ◽

Model Object ◽

Reduction Activity

AbstractAs low-cost electrocatalysts for oxygen reduction reaction applied to fuel cells and metal-air batteries, atomic-dispersed transition metal-nitrogen-carbon materials are emerging, but the genuine mechanism thereof is still arguable. Herein, by rational design and synthesis of dual-metal atomically dispersed Fe,Mn/N-C catalyst as model object, we unravel that the O2 reduction preferentially takes place on FeIII in the FeN4 /C system with intermediate spin state which possesses one eg electron (t2g4eg1) readily penetrating the antibonding π-orbital of oxygen. Both magnetic measurements and theoretical calculation reveal that the adjacent atomically dispersed Mn-N moieties can effectively activate the FeIII sites by both spin-state transition and electronic modulation, rendering the excellent ORR performances of Fe,Mn/N-C in both alkaline and acidic media (halfwave positionals are 0.928 V in 0.1 M KOH, and 0.804 V in 0.1 M HClO4), and good durability, which outperforms and has almost the same activity of commercial Pt/C, respectively. In addition, it presents a superior power density of 160.8 mW cm−2 and long-term durability in reversible zinc–air batteries. The work brings new insight into the oxygen reduction reaction process on the metal-nitrogen-carbon active sites, undoubtedly leading the exploration towards high effective low-cost non-precious catalysts.

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Generation of Fuel and Value-Added Chemicals from Carbon Dioxide (CO2)

SAMRIDDHI A Journal of Physical Sciences Engineering and Technology ◽

10.18090/samriddhi.v12i01.9 ◽

2020 ◽

Vol 12 (01) ◽

pp. 41-44

Author(s):

Pooja Srivastava

Keyword(s):

Carbon Dioxide ◽

Transition Metal ◽

Co2 Reduction ◽

Value Added ◽

Reduction Reaction ◽

Long Term Effects ◽

Industrial Chemicals ◽

Continuous Increase ◽

Carbon Dioxide Co2 ◽

Co2 Reduction Reaction

Despite its life-threatening long term effects, the continuous increase of carbon dioxide (CO2) in the environment requires immediate actions to control the accelerating climate change. An appealing solution to this problem is to utilize CO2 as feedstock to generate useful chemicals, e.g., fuel, hydrocarbons, and valuable chemicals. The chemical inertness of CO2 needs considerably large energy for its conversion into useful chemicals. Therefore, CO2 reduction reaction requires an effective catalyst for its conversion into fuel (methanol, methane) and industrial chemicals (syngas, formic acid). Recently, two-dimensional layers of early transition metal carbides and nitrides, called MXene, have shown potential for catalysis due to its exposed transition metal sites, and mechanical and chemical stability at high temperatures. Herein, the author presents the MXene as a potential heterogeneous catalyst for the CO2 reduction reaction (CRR), and the future scope in this currently developing field.

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