Modulating the Electrolyte Microenvironment in Electrical Double Layer for Boosting Electrocatalytic Nitrate Reduction to Ammonia

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(32)

Published: May 29, 2024

Abstract Electrochemical nitrate reduction reaction (NO 3 RR) is a promising approach to achieve remediation of nitrate‐polluted wastewater and sustainable production ammonia. However, it still restricted by the low activity, selectivity Faraday efficiency for ammonia synthesis. Herein, we propose an effective strategy modulate electrolyte microenvironment in electrical double layer (EDL) mediating alkali metal cations enhance NO RR performance. Taking bulk Cu as model catalyst, experimental study reveals that − ‐to‐NH performance different electrolytes follows trend Li + <Cs <Na <K . Theoretical studies illustrate proton transport rate activity rate‐determining step 2 ) increase order The cation effects are also general two typical nanostructured catalysts including copper/cuprous oxide nickel phosphides, achieving near‐100 % Faradaic over 99 conversion NH Furthermore, demonstrate can be converted high‐purity 4 Cl catalyst K ‐containing electrolyte.

Language: Английский

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Electrocatalytic Conversion of Nitrate Into Ammonia Through Heterogeneous Catalysis of NiMoO₄ and Cu/Cu₂O

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(36)

Published: April 5, 2024

Abstract Facilitating equilibrium in the nitrogen cycle, electrochemical nitrate reduction (NitRR) to ammonia stands as a carbon‐free method for synthesis. Copper‐based catalysts, renowned NitRR, face hurdle supplying sufficient hydrogen radicals (*H) efficient hydrogenation of NitRR intermediates. Addressing this, NiMoO 4 is leveraged an excellent *H donor, synergistically coupling it with copper‐based catalyst. The work introduces high‐performance /CuO nanowire (NW)/Copper foam (CF) catalyst achieving remarkable Faraday efficiency (FE) 98.8% and yield 0.8221 mmol cm −2 h −1 . Operating at −0.2 V versus reversible electrode (vs RHE) H‐type electrolytic cell, demonstrates exceptional stability over 20 h. Additionally, air stripping process enables collection NH Cl products, offering practical avenue converting waste nitrates into valuable products. In‐depth situ electrochemistry density‐functional theory (DFT) calculations affirm transformation CuO Cu/Cu 2 O during electrocatalytic process. catalyzes conversion nitrite, while , serving facilitates deoxidation other N intermediates on surface, effectively driving ammonia.

Language: Английский

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Achieving efficient urea electrosynthesis through improving the coverage of a crucial intermediate across a broad range of nitrate concentrations

Energy & Environmental Science, Journal Year: 2024, Volume and Issue: 17(14), P. 5183 - 5190

Published: Jan. 1, 2024

A novel Ru–Cu 9 Bi/CNT multi-site alloy is synthesised for electrocatalytic C–N coupling to generate urea across a broad range of NO 3 − concentrations. By improving the coverage key intermediate *NHO, ensure subsequent electrosynthesis urea.

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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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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Nanoflower‐Like CuPd/CuO Heterostructure for an Energy‐Output Electrocatalytic System Coupling Ammonia Electrosynthesis and Zinc‐Nitrate Battery

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

Published: March 18, 2025

Abstract Electrochemical nitrate reduction reaction (NO 3 RR) can effectively alleviate pollution and simultaneously realize ammonia electrosynthesis at room temperature. However, it remains a significant challenge for NO RR to achieve high Faradic efficiency in full concentration range. Herein, nanoflower‐like copper‐palladium alloy/CuO heterostructure (CuPd/CuO@NF) is successfully fabricated by the hydrothermal synthesis of CuO nanoflowers subsequent formation CuPd alloy. The as‐obtained CuPd/CuO@NF exhibits remarkable electrochemical performance − ‐N range from 20 1400 ppm, especially with conversion rate 97.8% NH selectivity 99.3% 94.2% yield 1.37 mmol h −1 cm −2 ppm. In‐situ Fourier transform infrared spectroscopy Raman spectra reveal that first catalyzes 2 , which rapidly reduced forming *NH, *NH OH intermediates. Density functional theory calculations suggest NHO route thermodynamically favorable. When applied zinc‐nitrate battery, demonstrates maximum power density 53.7 mW 99.9% 94.4%. This work offers valuable insights into design novel electrocatalysts batteries.

Language: Английский

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The Loss of Interfacial Water-Adsorbate Hydrogen Bond Connectivity Position Surface-Active Hydrogen as a Crucial Intermediate to Enhance Nitrate Reduction Reaction

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 20, 2024

The electrochemical nitrate reduction reaction (NO

Language: Английский

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Ultrathin 2D/2D MoS2/Bi2WO6 S-scheme heterojunction for boosting photocatalytic degradation of ciprofloxacin

Separation and Purification Technology, Journal Year: 2024, Volume and Issue: unknown, P. 129768 - 129768

Published: Sept. 1, 2024

Language: Английский

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Engineering Nickel Dopants in Atomically Thin Molybdenum Disulfide for Highly Efficient Nitrate Reduction to Ammonia

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

Published: Sept. 16, 2024

Abstract The electrocatalytic nitrate reduction reaction (NO 3 − RR) presents a promising pathway for achieving both ammonia (NH ) electrosynthesis and water pollutant removal simultaneously. Among various electrocatalysts explored, 2D materials have emerged as candidates due to their ability regulate electronic states active sites through doping. However, the impact of doping effects in on mechanism NO RR remains relatively unexplored. Here, Ni‐doped MoS 2 (Ni‐MoS nanosheets are investigated model system, demonstrating enhanced performance compared undoped counterparts. By controlling concentration, Ni‐MoS achieve remarkable faradic efficiency (FE) 92.3% NH at −0.3 V RHE with excellent stability. mechanistic studies reveal that elevation performances originates from generation more hydrogen acceleration nitrite facilitated by Ni Combining experimental observations theoretical calculations it is revealed appropriate level can enhance *NO adsorption strength, thereby facilitating subsequent steps. Together demonstration Zn−NO battery devices, work provides new insights into design regulation material catalysts efficient RR.

Language: Английский

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Copper–Nickel Oxide Nanosheets with Atomic Thickness for High‐Efficiency Sulfur Ion Electrooxidation Assisted Nitrate Electroreduction to Ammonia

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(48)

Published: Aug. 16, 2024

Abstract The nitrate electroreduction reaction (NO 3 RR) offers an eco‐friendly alternative to the Haber–Bosch technology for ammonia (NH ) synthesis. However, complex process and diverse products make efficient NH synthesis challenging. Therefore, rational design preparation of highly electrocatalysts are crucial NO RR. Herein, ultrathin copper‐nickel oxide (Cu‐NiO) nanosheets (Cu‐NiO UTNSs) synthesized via cyanogel‐NaBH 4 hydrolysis‐reduction method, which applied cathodic RR ‐assisted with anodic sulfur ion (S 2− oxidation (SOR) in electrolyzer. nanosheet structure, interaction between NiO Cu, formation oxygen vacancy contribute generating rich active sites, regulating electronic improving substance adsorption. Thus, Cu‐NiO UTNSs exhibit excellent electrocatalytic performance SOR. As a bifunctional UTNSs||Cu‐NiO electrolyzer, it can reach 10 mA cm −1 at only 0.1 V − ‐to‐NH conversion cathode S ‐to‐S 8 anode. This work provides promising approach producing value‐added chemicals low electrolysis voltage strategy pollutant treatment.

Language: Английский

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