Electrochemical Nitrate Reduction: Ammonia Synthesis and the Beyond

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(17)

Published: June 9, 2023

Natural nitrogen cycle has been severely disrupted by anthropogenic activities. The overuse of N-containing fertilizers induces the increase nitrate level in surface and ground waters, substantial emission oxides causes heavy air pollution. Nitrogen gas, as main component air, used for mass ammonia production over a century, providing enough nutrition agriculture to support world population increase. In last decade, researchers have made great efforts develop processes under ambient conditions combat intensive energy consumption high carbon associated with Haber-Bosch process. Among different techniques, electrochemical reduction reaction (NO

Language: Английский

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Breaking Local Charge Symmetry of Iron Single Atoms for Efficient Electrocatalytic Nitrate Reduction to Ammonia

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(39)

Published: July 22, 2023

The electrochemical conversion of nitrate pollutants into value-added ammonia is a feasible way to achieve artificial nitrogen cycle. However, the development electrocatalytic nitrate-to-ammonia reduction reaction (NO3- RR) has been hampered by high overpotential and low Faradaic efficiency. Here we develop an iron single-atom catalyst coordinated with phosphorus on hollow carbon polyhedron (denoted as Fe-N/P-C) NO3- RR electrocatalyst. Owing tuning effect atoms breaking local charge symmetry single-Fe-atom catalyst, it facilitates adsorption ions enrichment some key intermediates during process. Fe-N/P-C exhibits 90.3 % efficiency yield rate 17980 μg h-1 mgcat-1 , greatly outperforming reported Fe-based catalysts. Furthermore, operando SR-FTIR spectroscopy measurements reveal pathway based observed under different applied potentials durations. Density functional theory calculations demonstrate that optimized free energy ascribed asymmetric atomic interface configuration, which achieves optimal electron density distribution. This work demonstrates critical role atomic-level precision modulation heteroatom doping for RR, providing effective strategy improving catalytic performance single atom catalysts in reactions.

Language: Английский

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Geometric and Electronic Engineering of Atomically Dispersed Copper‐Cobalt Diatomic Sites for Synergistic Promotion of Bifunctional Oxygen Electrocatalysis in Zinc–Air Batteries

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(25)

Published: April 11, 2023

The development of rechargeable zinc-air batteries is heavily dependent on bifunctional oxygen electrocatalysts to offer exceptional reduction/evolution reaction (ORR/OER) activities. However, the design such with high activity and durability challenging. Herein, a strategy proposed create an electrocatalyst comprised copper-cobalt diatomic sites highly porous nitrogen-doped carbon matrix (Cu-Co/NC) abundantly accessible metal optimal geometric electronic structures. Experimental findings theoretical calculations demonstrate that synergistic effect Cu-Co dual-metal metal-N4 coordination induce asymmetric charge distributions moderate adsorption/desorption behavior intermediates. This exhibits extraordinary electrocatalytic activities in alkaline media, half-wave potential 0.92 V for ORR low overpotential 335 mV at 10 mA cm-2 OER. In addition, it demonstrates acidic (0.85 V) neutral (0.74 media. When applied battery, achieves operational performance outstanding (510 h), ranking as one most efficient reported date. work importance engineering isolated boosting electrochemical energy devices.

Language: Английский

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Recent Advances in Electrocatalysts for Efficient Nitrate Reduction to Ammonia

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(43)

Published: June 25, 2023

Abstract Ammonia as an irreplaceable chemical has been widely demanded to keep the sustainable development of modern society. However, its industrial production consumes huge energy and releases extraordinary green‐house gases, leading various environmental issues. To achieve green ammonia is a great challenge that extensively pursued recently. In review, most promising strategy, electrochemical nitrate reduction reaction (e‐NO 3 RR) for purpose comprehensively investigated give full understanding mechanism provide guidance future directions. Particularly, electrocatalysts focused realize high yield rate Faraday efficiency applications. The recent‐developed catalysts, including noble metallic materials, alloys, metal compounds, single‐metal‐atom metal‐free are systematically discussed review effects factors on catalytic performance in e‐NO RR. Accordingly, strategies, defects engineering, coordination environment modulating, surface controlling, hybridization, carefully improve performance, such intrinsic activity selectivity. Finally, perspectives challenges given out. This shall insightful advanced systems efficiently industry.

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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Potential-Induced Synthesis and Structural Identification of Oxide-Derived Cu Electrocatalysts for Selective Nitrate Reduction to Ammonia

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(11), P. 7529 - 7537

Published: May 19, 2023

Developing effective electrocatalysts for nitrate reduction to ammonia is paramount synthesis while addressing the water pollutant issue. Identifying active structure and its correlation with catalytic behavior during reaction process essential challenging rational design of advanced electrocatalysts. Herein, starting from Cu2O particles controllable crystal facets, electrochemically reconstituted Cu/Cu2O was fabricated as a suitable system, relationship between chemical state copper product selectivity in studied. At −0.9 V versus reversible hydrogen electrode, oxide-derived Cu0 (OD-Cu) cube achieved high Faradaic efficiency 93.9% productivity up 219.8 μmol h–1 cm–2, surpassing those most Cu-based catalysts. In situ Raman analysis, well-designed pulsed electrolysis experiments, theoretical calculations showed that preferentially produced on OD-Cu at potentials presence interface favored nitrite formation low potentials. The originated enhanced adsorption lower barrier potential-determining step (*NH3 → NH3). This work presents an strategy boost electrocatalysis offers insight into real phase corresponding

Language: Английский

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Progress in metal-organic-framework-based single-atom catalysts for environmental remediation

Coordination Chemistry Reviews, Journal Year: 2022, Volume and Issue: 474, P. 214855 - 214855

Published: Oct. 4, 2022

Language: Английский

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Conjugated Coordination Polymer as a New Platform for Efficient and Selective Electroreduction of Nitrate into Ammonia

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(10)

Published: Jan. 18, 2023

Electroreduction of nitrate into ammonia (NRA) provides a sustainable route to convert the widespread pollutants high-value-added products under ambient conditions, which unfortunately suffers from unsatisfactory selectivity due competitive hydrogen evolution reaction (HER). Previous strategies modifying metal sites catalysts often met dilemma for simultaneously promoting activity and toward NRA. Here, general strategy is reported enable an efficient selective NRA process through coordination modulation single-atom tailor local proton concentration at catalyst surface. By contrast, two analogous Ni-single-atom enriched conjugated polymers (NiO4 -CCP NiN4 -CCP) with different motifs are investigated proof-of-concept study. The NiO4 exhibits yield rate as high 1.83 mmol h-1 mg-1 Faradaic efficiency 94.7% current density 125 mA cm-2 , outperforming catalyst. These experimental theoretical studies both suggest that can not only accelerate by adjusting adsorption energies intermediates on but also inhibit HER regulating migration contributions metal-hydrated cations adsorbed surface, thus achieving simultaneous enhancement activity.

Language: Английский

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Unveiling the Reaction Mechanism of Nitrate Reduction to Ammonia Over Cobalt-Based Electrocatalysts

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(19), P. 12976 - 12983

Published: April 3, 2024

Electrocatalytic reduction of nitrate to ammonia (NRA) has emerged as an alternative strategy for sewage treatment and generation. Despite excellent performances having been achieved over cobalt-based electrocatalysts, the reaction mechanism well veritable active species across a wide potential range are still full controversy. Here, we adopt CoP, Co, Co3O4 model materials solve these issues. CoP evolves into core@shell structured CoP@Co before NRA. For Co catalysts, three-step relay is carried out superficial dynamical Coδ+ under low overpotential, while continuous hydrogenation from unveiled high overpotential. In comparison, stable steadily catalyze range. As result, exhibit much higher NRA activity than especially Moreover, performance although they experience same mechanism. A series characterizations clarify reason enhancement highlighting that core donates abundant electrons species, leading generation more hydrogen nitrogen-containing intermediates.

Language: Английский

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Atomic Co─P Catalytic Pair Drives Efficient Electrochemical Nitrate Reduction to Ammonia

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(28)

Published: March 3, 2024

Abstract Electrochemically reducing nitrate (NO 3 − ), a common water pollutant, to valuable ammonia (NH ) offers green, sustainable, and decentralized route for synthesis. Electrochemical reduction reaction RR) involves two crucial steps: deoxygenation followed by nitrite hydrogenation; in particular, the hydrogenation is rate‐determining step (RDS) NO RR. In this work, an atomically dispersed cobalt‐phosphorus (Co─P) catalytic pair (CP) with strong electronic coupling reported. The Co site Co─P CP effectively activates , while P facilitates dissociation release H + synergistically enhancing thermodynamic kinetic performance of electrochemical ammonia.

Language: Английский

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