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

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 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.

Language: Английский

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Unveiling Ionized Interfacial Water‐Induced Localized H* Enrichment for Electrocatalytic Nitrate Reduction

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 64(1)

Published: Sept. 4, 2024

Electrocatalytic nitrate reduction reaction (NO

Language: Английский

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Interfacial Water Regulation for Nitrate Electroreduction to Ammonia at Ultralow Overpotentials

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

Abstract Nitrate electroreduction is promising for achieving effluent waste‐water treatment and ammonia production with respect to the global nitrogen balance. However, due impeded hydrogenation process, high overpotentials need be surmounted during nitrate electroreduction, causing intensive energy consumption. Herein, a hydroxide regulation strategy developed optimize interfacial H 2 O behavior accelerating conversion of at ultralow overpotentials. The well‐designed Ru─Ni(OH) electrocatalyst shows remarkable efficiency 44.6% +0.1 V versus RHE nearly 100% Faradaic NH 3 synthesis 0 RHE. In situ characterizations theoretical calculations indicate that Ni(OH) can regulate structure promoted dissociation process contribute spontaneous hydrogen spillover boosting NO − Ru sites. Furthermore, assembled rechargeable Zn‐NO /ethanol battery system exhibits an outstanding long‐term cycling stability charge–discharge tests high‐value‐added ammonium acetate, showing great potential simultaneously removal, conversion, chemical synthesis. This work not only provide guidance in extensive reactions but also inspire design novel hybrid flow multiple functions.

Language: Английский

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

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 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

Language: Английский

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Rational design of precatalysts and controlled evolution of catalyst-electrolyte interface for efficient hydrogen production

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 22, 2025

The concept of precatalyst is widely accepted in electrochemical water splitting, but the role activation and resulted changes electrolyte composition often overlooked. Here, we elucidate impact potential-dependent for both using Co2Mo3O8 as a model system. Potential-dependent reconstruction results an electrochemically stable Co(OH)2@Co2Mo3O8 catalyst additional Mo dissolved MoO42− into electrolyte. Co(OH)2/Co2Mo3O8 interface accelerates Volmer reaction negative potentials induced Mo2O72− (from MoO42−) further enhances proton adsorption H2 desorption. Leveraging these insights, well-designed MoO42−/Mo2O72− modified achieves Faradaic efficiency 99.9% yield 1.85 mol h−1 at −0.4 V versus reversible hydrogen electrode (RHE) generation. Moreover, it maintains over one month approximately 100 mA cm−2, highlighting its industrial suitability. This work underscores significance understanding on evolution design. properties electrocatalysis crucial authors report efficient transition metal production by manipulating composition.

Language: Английский

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

Journal of Hazardous Materials, Journal Year: 2025, Volume and Issue: 492, P. 138266 - 138266

Published: April 15, 2025

Language: Английский

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A Copper–Zinc Cyanamide Solid-Solution Catalyst with Tailored Surface Electrostatic Potentials Promotes Asymmetric N-Intermediate Adsorption in Nitrite Electroreduction

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: 147(9), P. 8012 - 8023

Published: Feb. 18, 2025

The electrocatalytic nitrite reduction (NO2RR) converts nitrogen-containing pollutants to high-value ammonia (NH3) under ambient conditions. However, its multiple intermediates and multielectron coupled proton transfer process lead low activity NH3 selectivity for the existing electrocatalysts. Herein, we synthesize a solid-solution copper-zinc cyanamide (Cu0.8Zn0.2NCN) with localized structure distortion tailored surface electrostatic potential, allowing asymmetric binding of NO2-. It exhibits outstanding NO2RR performance Faradaic efficiency ∼100% an yield 22 mg h-1 cm-2, among best such process. Theoretical calculations in situ spectroscopic measurements demonstrate that Cu-Zn sites coordinated linear polarized [NCN]2- could transform symmetric [Cu-O-N-O-Cu] CuNCN-NO2- [Cu-N-O-Zn] configuration Cu0.8Zn0.2NCN-NO2-, thus enhancing adsorption bond cleavage. A paired electro-refinery Cu0.8Zn0.2NCN cathode reaches 2000 mA cm-2 at 2.36 V remains fully operational industrial-level 400 >140 h production rate ∼30 mgNH3 cm-2. Our work opens new avenue tailoring potentials using strategy advanced electrocatalysis.

Language: Английский

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

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 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

Language: Английский

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Self-Triggering a Locally Alkaline Microenvironment of Co₄Fe₆ for Highly Efficient Neutral Ammonia Electrosynthesis

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 28, 2025

Electrochemical nitrate reduction reaction (eNO3-RR) to ammonia (NH3) holds great promise for the green treatment of NO3- and ambient NH3 synthesis. Although Fe-based electrocatalysts have emerged as promising alternatives, their excellent eNO3-RR-to-NH3 activity is usually limited harsh alkaline electrolytes or alloying noble metals with Fe in sustainable neutral electrolytes. Herein, we demonstrate an unusual self-triggering localized alkalinity Co4Fe6 electrocatalyst efficient media, which breaks down conventional pH-dependent kinetics restrictions shows a 98.6% Faradaic efficiency (FE) 99.9% selectivity at -0.69 V vs RHE. The synergetic Co-Fe dual sites were demonstrated enable optimal free energies species balance water dissociation protonation adsorbed NO2-. Notably, can attain high current density 100 mA cm-2 FE surpassing 96% long-term stability over 500 h membrane electrode assembly (MEA) electrolyzer. This work provides insight into tailoring self-reinforced local-alkalinity on alloy thus avoids practical upcycling technology.

Language: Английский

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Accelerating the Transformation of Active β‐NiOOH on NiFe Layered Double Hydroxide via Cation–anion Collaborative Coordination for Alkaline Water Oxidation at High Current Densities

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: April 7, 2025

Abstract The NiFe‐based layered double hydroxides (LDH) undergo surface reconstruction, generating metal hydroxyl oxides that act as active species during the alkaline oxygen evolution reaction (OER). However, sluggish reconstruction process and excessive oxidation at higher anodic potentials frustrate OER activity stability. Herein, a cation–anion collaborative coordination strategy is harnessed to build (Ni, Fe)─S─Zn structures in NiFe LDH on nickel foam (S‐NiFeZn LDH/NF), which lowers energy barrier aids forming highly β‐NiOOH process. Meanwhile, also optimize adsorption of oxygen‐containing intermediates, enhancing kinetics. As result, S‐NiFeZn LDH/NF achieves low overpotentials 201 mV 10 mA cm −2 293 500 1.0 m KOH. Moreover, cell assembled with anode commercial NiMo cathode demonstrates excellent overall water splitting activity, voltages 1.62 1.81 V KOH, exhibits ultralong‐term durability over h , even operating stably for 200 an electrolyzer under industrial conditions (30% KOH 80 °C).

Language: Английский

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