Elucidating electrochemical nitrate and nitrite reduction over atomically-dispersed transition metal sites

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: July 28, 2023

Electrocatalytic reduction of waste nitrates (NO3-) enables the synthesis ammonia (NH3) in a carbon neutral and decentralized manner. Atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts demonstrate high catalytic activity uniquely favor mono-nitrogen products. However, reaction fundamentals remain largely underexplored. Herein, we report set 14; 3d-, 4d-, 5d- f-block M-N-C catalysts. The selectivity NO3- to NH3 media, with specific focus on deciphering role NO2- intermediate cascade, reveals strong correlations (R=0.9) between for NH3. Moreover, theoretical computations reveal associative/dissociative adsorption pathways evolution, over normal M-N4 sites their oxo-form (O-M-N4) oxyphilic metals. This work provides platform designing multi-element NO3RR cascades single-atom or hybridization extended surfaces.

Language: Английский

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Addressing nitrogenous gases from croplands toward low-emission agriculture

npj Climate and Atmospheric Science, Journal Year: 2022, Volume and Issue: 5(1)

Published: June 2, 2022

Abstract The use of nitrogen fertilizers in agriculture produces significant quantities nitrogenous gases including ammonia, nitric oxide, and nitrous oxide. Through better farmland management practices, the emission can be reduced while realizing clean water environment climate-smart agriculture. In this article, we first provided an overview international movements on reducing gas emissions from farmlands. Then, summarized effect agricultural practices efficiency for various crops, evaluated their emissions. results indicated importance implementing site-specific sustainable to enhance efficiency, thus mitigate We also addressed impact activities cropland cycles, highlighted need perform systematic trade-off evaluations with a well-defined scope maximize environmental benefits maintain ecosystem services. Lastly, proposed three priority directions by moving toward low-emission

Language: Английский

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Mesoporous PdN Alloy Nanocubes for Efficient Electrochemical Nitrate Reduction to Ammonia

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(1)

Published: Oct. 25, 2022

Developing highly active and selective electrocatalysts for electrochemical nitrate reduction reaction (NITRR) is very important synthesizing recyclable ammonia (NH3 ) in an economic environmentally friendly manner. Despite some encouraging progress, their activity selectivity have been remarkably slower than expected. In this manuscript, mesoporous palladium-nonmetal (meso-PdX) nanocubes (NCs) are reported as a new series of efficient electrocatalysis to NH3 . The samples feature uniformly alloyed compositions penetrated mesopores with abundant sites optimized electronic structures. best meso-PdN NCs hold outstanding NITRR remarkable Faradaic efficiency 96.1% yield rate 3760 µg h-1 mg-1 , suppressing the state-of-the-art electrocatalysts. Meanwhile, electrocatalytically stable, retaining well NO3- -to-NH3 more 20 cycles. Detailed mechanism studies ascribe superior performance combined compositional structural synergies that not only promote adsorption (reactivity) desorption but also increase retention time key intermediates deeper through eight-electron pathway.

Language: Английский

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Boosting Electrocatalytic Nitrate Reduction to Ammonia via Promoting Water Dissociation

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(16), P. 10846 - 10854

Published: Aug. 2, 2023

Electrocatalytic nitrate reduction reaction (NO3–RR) opens opportunities for ammonia production. The sluggish kinetics of this multielectron and multiproton process has been regarded as the key issue. Herein, we report a Cu1Co5 alloy electrocatalytic NO3–RR to NH3. It achieves high current density (453 mA cm–2) Faradaic efficiency (96.2%) NH3 production at 0.075 V vs RHE, with half-cell energy 44.9%, higher than those Cu, Co, other Co-based alloys, is among highest value reported. We found that interaction between Cu Co reorganizes their electronic structure in alloys. NO3– adsorption switches spontaneous process, *NO → *N *NH *NH2 processes are promoted. Importantly, water dissociation concerted transformation N-species proven be rate-determining, which facilitated on sites essential enhanced NO3–RR. This inspires us strategy designing more efficient catalysts under alkaline condition by promoting H2O process.

Language: Английский

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Weakened d–p orbital hybridization inin situreconstructed Ru/β-Co(OH)₂heterointerfaces for accelerated ammonia electrosynthesis from nitrates

Energy & Environmental Science, Journal Year: 2023, Volume and Issue: 16(6), P. 2483 - 2493

Published: Jan. 1, 2023

Electron-deficient Ru sites at Ru/Co(OH) 2 heterointerfaces weaken the d–p orbital hybridization ability and further facilitate desorption of ammonia intermediates, thereby achieving ultrahigh nitrate electroreduction activity towards ammonia.

Language: Английский

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Turning Waste into Wealth: Sustainable Production of High-Value-Added Chemicals from Catalytic Coupling of Carbon Dioxide and Nitrogenous Small Molecules

ACS Nano, Journal Year: 2022, Volume and Issue: 16(11), P. 17911 - 17930

Published: Oct. 31, 2022

Carbon neutrality is one of the central topics not only scientific community but also majority human society. The development highly efficient carbon dioxide (CO2) capture and utilization (CCU) techniques expected to stimulate routes concepts go beyond fossil fuels provide more economic benefits for a carbon-neutral economy. While various single-carbon (C1) multi-carbon (C2+) products have been selectively produced date, scope CCU can be further expanded valuable chemicals simple species by integration nitrogenous reactants into CO2 reduction. In this Review, research progress toward sustainable production high-value-added (urea, methylamine, ethylamine, formamide, acetamide, glycine) from catalytic coupling small molecules (NH3, N2, NO3–, NO2–) highlighted. C–N bond formation key mechanistic step in N-integrated reduction, so we focus on possible pathways starting reduction processes as well attributes that enable coupling. We propose directions prospects field, aiming inspire future investigations achieve comprehensive improvement performance product systems.

Language: Английский

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High-efficiency ammonia electrosynthesis on self-supported Co2AlO4 nanoarray in neutral media by selective reduction of nitrate

Chemical Engineering Journal, Journal Year: 2022, Volume and Issue: 435, P. 135104 - 135104

Published: Feb. 5, 2022

Language: Английский

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Near-unity electrochemical conversion of nitrate to ammonia on crystalline nickel porphyrin-based covalent organic frameworks

Energy & Environmental Science, Journal Year: 2022, Volume and Issue: 16(1), P. 201 - 209

Published: Nov. 23, 2022

A novel 2D nickel porphyrin-based covalent organic framework is fabricated as an efficient nitrate reduction electrocatalyst that shows a great selectivity of ∼90% under mild overpotential with remarkable production rate and turnover frequency.

Language: Английский

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Metal-organic framework derived carbon-supported bimetallic copper-nickel alloy electrocatalysts for highly selective nitrate reduction to ammonia

Journal of Colloid and Interface Science, Journal Year: 2022, Volume and Issue: 614, P. 405 - 414

Published: Jan. 25, 2022

Language: Английский

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Batch-Scale Synthesis of Nanoparticle-Agminated Three-Dimensional Porous Cu@Cu₂O Microspheres for Highly Selective Electrocatalysis of Nitrate to Ammonia

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(14), P. 10299 - 10307

Published: June 29, 2022

The electrochemical nitrate reduction reaction (NITRR), which converts to ammonia, is promising for artificial ammonia synthesis at mild conditions. However, the lack of favorable electrocatalysts has hampered its large-scale applications. Herein, we report batch-scale three-dimensional (3D) porous Cu@Cu2O microspheres (Cu@Cu2O MSs) composed fine nanoparticles (NPs) using a convenient electric explosion method with outstanding activity and stability ammonia. Density functional theory (DFT) calculations revealed that Cu2O (111) facets could facilitate formation *NO3H *NO2H intermediates suppress hydrogen evolution (HER), resulting in high selectivity NITRR. Moreover, 3D structure MSs facilitates electrolyte penetration increases localized concentration reactive species As expected, obtained exhibited an ultrahigh NH3 production rate 327.6 mmol·h-1·g-1cat. (which superior Haber-Bosch process typical yield <200 mmol h-1g-1cat.), maximum Faradaic efficiency 80.57%, remarkable NITRR under ambient Quantitative 15N isotope labeling experiments indicated synthesized originated from nitrate. Achieving low-cost high-performance realization selective toward synthesis.

Language: Английский

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