Electrocatalytic Nitrate and Nitrite Reduction toward Ammonia Using Cu₂O Nanocubes: Active Species and Reaction Mechanisms

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(14), С. 9665 - 9678

Опубликована: Апрель 1, 2024

The electrochemical reduction of nitrate (NO3–) and nitrite (NO2–) enables sustainable, carbon-neutral, decentralized routes to produce ammonia (NH3). Copper-based materials are promising electrocatalysts for NOx– conversion NH3. However, the underlying reaction mechanisms role different Cu species during catalytic process still poorly understood. Herein, by combining quasi in situ X-ray photoelectron spectroscopy (XPS) operando absorption (XAS), we unveiled that is mostly metallic form highly selective NO3–/NO2– On contrary, Cu(I) predominant a potential region where two-electron NO3– NO2– major reaction. Electrokinetic analysis Raman was also used propose possible steps intermediates leading NH3, respectively. This work establishes correlation between performance dynamic changes chemical state Cu, provides crucial mechanistic insights into pathways electrocatalytic reduction.

Язык: Английский

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Efficient tandem electroreduction of nitrate into ammonia through coupling Cu single atoms with adjacent Co3O4

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Апрель 29, 2024

Abstract The nitrate (NO 3 − ) electroreduction into ammonia (NH represents a promising approach for sustainable NH synthesis. However, the variation of adsorption configurations renders great difficulties in simultaneous optimization binding energy intermediates. Though extensively reported Cu-based electrocatalysts benefit NO adsorption, one key issues lies accumulation nitrite 2 due to its weak resulting rapid deactivation catalysts and sluggish kinetics subsequent hydrogenation steps. Here we report tandem electrocatalyst by combining Cu single atoms with adjacent Co O 4 nanosheets boost . obtained catalyst exhibits yield rate 114.0 mg $${}_{{{{{{\rm{NH}}}}}}_3}$$ NH 3 h −1 cm −2 , which exceeds previous values catalysts. Mechanism investigations unveil that combination regulates configuration strengthens thus accelerating

Язык: Английский

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Enhancing Compatibility of Two‐Step Tandem Catalytic Nitrate Reduction to Ammonia Over P‐Cu/Co(OH)₂

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Сен. 11, 2024

Abstract Electrochemical nitrate reduction reaction (NO 3 RR) is a promising approach to realize ammonia generation and wastewater treatment. However, the transformation from NO − NH involves multiple proton‐coupled electron transfer processes by‐products 2 , H etc.), making high selectivity challenge. Herein, two‐phase nanoflower P‐Cu/Co(OH) electrocatalyst consisting of P‐Cu clusters P‐Co(OH) nanosheets designed match two‐step tandem process ) more compatible, avoiding excessive accumulation optimizing whole reaction. Focusing on initial 2e process, inhibited * desorption Cu sites in gives rise appropriate released electrolyte. Subsequently, exhibits superior capacity for trapping transforming desorbed during latter 6e due thermodynamic advantage contributions active hydrogen. In 1 m KOH + 0.1 leads yield rate 42.63 mg h cm Faradaic efficiency 97.04% at −0.4 V versus reversible hydrogen electrode. Such well‐matched achieves remarkable synthesis performance perspective catalytic reaction, offering novel guideline design RR electrocatalysts.

Язык: Английский

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Modulating the Surface Concentration and Lifetime of Active Hydrogen in Cu-Based Layered Double Hydroxides for Electrocatalytic Nitrate Reduction to Ammonia

ACS Catalysis, Год журнала: 2024, Номер 14(16), С. 12042 - 12050

Опубликована: Июль 29, 2024

Strategies incorporating heterometals to introduce surface-active hydrogen (*H) have been extensively utilized enhance the electrocatalytic activity of Cu-based catalysts in nitrate reduction reaction (NitRR). However, a comprehensive understanding *H behavior and its specific impact on regulating NitRR pathway remains elusive, particularly quantitative manner. In this study, we prepared group layered double hydroxides (LDHs) as model with diverse concentrations lifetimes. Our findings reveal that LDHs is highly dependent species could be modulated by incorporated heterometallic sites. Specifically, conducted situ analysis different LDH using time-resolved scanning electrochemical microscopy. The surface concentration lifetime at various applied potentials were quantified, enabling us establish relationship between performance. Therefore, optimal performance was achieved CuNi-LDHs, exhibiting faradaic efficiency 94.6% yield rate 2.7 mg h–1 cm–2 because appropriate lifetime. Additionally, observe trend CuNi > CuCo Cu CuRu CuFe CuMg terms for NH3 production. These results suggest effectively utilizing stable produced catalyst, one would allow favorable performance, offering promising strategy other hydrogenation reactions.

Язык: Английский

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Cu/Cu_xO/Graphdiyne Tandem Catalyst for Efficient Electrocatalytic Nitrate Reduction to Ammonia

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Июнь 17, 2024

The electrocatalytic reduction reaction of nitrate (NO

Язык: Английский

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Matched Kinetics Process Over Fe₂O₃‐Co/NiO Heterostructure Enables Highly Efficient Nitrate Electroreduction to Ammonia

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(15)

Опубликована: Янв. 31, 2024

Abstract Tandem nitrate electroreduction reaction (NO 3 − RR) is a promising method for green ammonia (NH ) synthesis. However, the mismatched kinetics processes between NO ‐to‐NO 2 and ‐to‐NH results in poor selectivity NH excess evolution electrolyte solution. Herein, Ni 2+ substitution strategy developing oxide heterostructure Co/Fe layered double oxides (LDOs) was designed employed as tandem electrocataltysts RR. (Co 0.83 0.16 Fe exhibited high yield rate of 50.4 mg ⋅ cm −2 h −1 with Faradaic efficiency 97.8 % at −0.42 V vs. reversible hydrogen electrode (RHE) pulsed electrolysis test. By combining situ / operando characterization technologies theoretical calculations, we observed strong over Fe, playing dual role RR by i) modifying electronic behavior Co, ii) serving complementary site active (*H) supply. Therefore, adsorption capacity *NO its subsequent hydrogenation on Co sites became more thermodynamically feasible. This study shows that promotes provides insights into design electrocatalysts evolution.

Язык: Английский

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Interface Engineering on Heterostructural Nanosheets for Efficient Electrocatalytic-Paired Upcycling of Waste Plastics and Nitrate

ACS Catalysis, Год журнала: 2024, Номер unknown, С. 18095 - 18106

Опубликована: Ноя. 22, 2024

Язык: Английский

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Ammonia electrosynthesis from nitrate using a stable amorphous/crystalline dual-phase Cu catalyst

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 21, 2025

Renewable energy-driven electrocatalytic nitrate reduction reaction presents a low-carbon and sustainable route for ammonia synthesis under mild conditions. Yet, the practical application of this process is currently hindered by unsatisfactory activity long-term stability. Herein we achieve high-rate electrosynthesis using stable amorphous/crystalline dual-phase Cu catalyst. The partial current density formation rate reach 3.33 ± 0.005 A cm-2 15.5 0.02 mmol h-1 at low cell voltage 2.6 0.01 V, respectively. Remarkably, catalyst can maintain production with Faradaic efficiency around 90% high 1.5 up to 300 h. scale-up demonstration an electrode size 100 cm2 achieves as 11.9 0.5 g total 160 A. impressive performance ascribed presence amorphous domains which promote adsorption hydrogenation nitrogen-containing intermediates, thus improving kinetics formation. This work underscores importance stabilizing metastable structures reactivity

Язык: Английский

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Cu‐Co Dual Sites Tandem Synergistic Effect Boosting Neutral Low Concentration Nitrate Electroreduction to Ammonia

Advanced Science, Год журнала: 2025, Номер unknown

Опубликована: Фев. 17, 2025

Abstract Electrochemical nitrate reduction reaction (NO 3 − RR) has emerged as an alternative strategy for wastewater treatment and ammonia production in neutral low‐concentration nitrate. However, the electrocatalyst faces challenge of limited NO distribution deficient active hydrogen (H ads ) on catalyst surface resulting from low concentration difficulty water splitting under conditions. Here, a Cu‐Co dual sites tandem synergistic catalysis mechanism been proposed by doping Cu into CoP to facilitate adsorption conversion accelerate leading significantly high RR performance. The designed Cu‐CoP exhibits yield 7.65 mg h −1 cm −2 Faraday efficiency 85.1% at −1.0 V (10 m M ), which is highest reported data. In situ characterization theoretical calculations confirm effect, site favors activation form 2 , concurrently modulates electronic structure Co with optimized H enhanced

Язык: Английский

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Co-Cu dual active sites for synergistic electrochemical nitrate reduction to ammonia

Journal of Hazardous Materials, Год журнала: 2025, Номер 492, С. 138266 - 138266

Опубликована: Апрель 15, 2025

Язык: Английский

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