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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Pulsed electroreduction of low-concentration nitrate to ammonia

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

Published: Nov. 14, 2023

Electrocatalytic nitrate (NO3-) reduction to ammonia (NRA) has emerged as an alternative strategy for effluent treatment and production. Despite significant advancements that have been achieved in this field, the efficient conversion of low-concentration at low overpotential remains a formidable challenge. This challenge stems from sluggish reaction kinetics caused by limited distribution negatively charged NO3- vicinity working electrode competing side reactions. Here, pulsed potential approach is introduced overcome these issues. A good NRA performance (Faradaic efficiency: 97.6%, yield rate: 2.7 mmol-1 h-1 mgRu-1, 96.4%) (≤10 mM) reduction, obviously exceeding potentiostatic test 65.8%, 1.1 54.1%). The combined results situ characterizations finite element analysis unveil enhancement mechanism periodic appearance anodic can significantly optimize adsorption configuration key *NO intermediate increase local concentration. Furthermore, our research implies effective rational design precise manipulation processes, potentially extending its applicability broader range catalytic applications.

Language: Английский

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Modulating the Active Hydrogen Adsorption on Fe─N Interface for Boosted Electrocatalytic Nitrate Reduction with Ultra‐Long Stability

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(46)

Published: July 25, 2023

The electrocatalytic reduction of nitrate (NO3- ) to nitrogen (N2 is an environmentally friendly approach for efficient N-cycle management (toward a nitrogen-neutral cycle). However, poor catalyst durability and the competitive hydrogen evolution reaction significantly impede its practical application. Interface-chemistry engineering, utilizing close relationship between surface/interface microenvironment electron/proton transfer process, has facilitated development catalysts with high intrinsic activity physicochemical durability. This study reports synthesis nitrogen-doped carbon-coated rice-like iron nitride (RL-Fe2 N@NC) electrocatalyst excellent nitrate-reduction (high N2 selectivity (≈96%) NO3- conversion (≈86%)). According detailed mechanistic investigations by in situ tests theoretical calculations, strong hydrogenation ability enhanced enrichment system synergistically contribute rapid nitrogen-containing species, increasing reducing occurrence competing hydrogen-evolution side reaction. Moreover, RL-Fe2 N@NC shows stability, retaining good -to-N2 electrocatalysis more than 40 cycles (one cycle per day). paper could guide interfacial design Fe-based composite nanostructures reduction, facilitating shift toward neutrality.

Language: Английский

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Free-standing membrane incorporating single-atom catalysts for ultrafast electroreduction of low-concentration nitrate

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(11)

Published: March 6, 2023

The release of wastewaters containing relatively low levels nitrate (NO3-) results in sufficient contamination to induce harmful algal blooms and elevate drinking water NO3- concentrations potentially hazardous levels. In particular, the facile triggering by ultra-low necessitates development efficient methods for destruction. However, promising electrochemical suffer from weak mass transport under reactant concentrations, resulting long treatment times (on order hours) complete this study, we present flow-through electrofiltration via an electrified membrane incorporating nonprecious metal single-atom catalysts reduction activity enhancement selectivity modification, achieving near-complete removal concentration (10 mg-N L-1) with a residence time only few seconds s). By anchoring Cu single atoms supported on N-doped carbon nanotube interwoven framework, fabricate free-standing carbonaceous featuring high conductivity, permeability, flexibility. achieves over 97% N2 86% single-pass electrofiltration, which is significant improvement flow-by operation (30% 7% selectivity). This performance attributed greater adsorption nitric oxide molecular collision frequency coupled balanced supply atomic hydrogen through H2 dissociation during electrofiltration. Overall, our findings provide paradigm applying improve rate purification.

Language: Английский

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

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: April 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

Language: Английский

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Elucidating the Intrinsic Activity and Selectivity of Cu for Nitrate Electroreduction

ACS Energy Letters, Journal Year: 2023, Volume and Issue: 8(9), P. 3658 - 3665

Published: Aug. 4, 2023

Cu-based catalysts have been widely explored for the electrochemical nitrate reduction reaction (NO3RR), while intrinsic activity and selectivity of Cu metal NO3RR remain ambiguous, preventing a genuine comparison performance. Here we use polycrystalline foils benchmarking elucidate impact often overlooked factors on NO3RR, including facet exposure, concentration, electrode surface area. An electropolished foil exhibits higher to NH3 than wet-etched foil, benefiting from greater exposure Cu(100) facets that are more favorable NO3RR. While shows no apparent dependence it increases monotonically with area, which is attributed promoted conversion intermediately produced NO2– larger electrode, as validated by 15N isotope labeling experiment. Our work provides mechanistic insights toward rational design electrocatalysts.

Language: Английский

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Relay Catalysis of Fe and Co with Multi‐Active Sites for Specialized Division of Labor in Electrocatalytic Nitrate Reduction Reaction

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

Published: April 8, 2024

Abstract Electrocatalytic nitrate reduction reaction (NO 3 RR) driven by renewable energy is a promising technology for the removal of nitrate‐containing wastewater. However, sluggish kinetics resulted from complex proton‐coupled electron transfer and various intermediates remain key barriers large‐scale application NO RR. Herein, tactic reported to raise rate RR increase selectivity N 2 using bimetal catalyst: Co inclined act on steps needed in process, rate‐determining step (RDS: *NO , asterisk means intermediates) subsequent *N hydrogenation as well Fe exhibits efficient activity selectivity‐ determining (SDS: then ) via relay catalysis mechanism. A efficiency 78.5% an ultra‐long cycle stability 60 cycles (12 h per cycle) are achieved FeCo alloy confined with nitrogen‐doped porous carbon nanofibers (FeCo‐NPCNFs). DFT calculations unveil that introduction active site not only regulates d‐band center alloy, optimizes adsorption intermediates, but also has strong capacity supply hydrogen species. Clearly, this study elucidates effects bimetallic performance electrocatalytic offers avenues designing Fe‐based catalysts realize nitrogen‐neutral cycle.

Language: Английский

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Electrochemical nitrate reduction to ammonia with cation shuttling in a solid electrolyte reactor

Nature Catalysis, Journal Year: 2024, Volume and Issue: 7(9), P. 1032 - 1043

Published: Aug. 12, 2024

Language: Английский

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Cu1‐Fe Dual Sites for Superior Neutral Ammonia Electrosynthesis from Nitrate

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(31)

Published: May 21, 2024

Abstract The electrochemical nitrate reduction reaction (NO 3 RR) is able to convert − ) into reusable ammonia (NH ), offering a green treatment and resource utilization strategy of wastewater synthesis. conversion NO NH undergoes water dissociation generate active hydrogen atoms nitrogen‐containing intermediates hydrogenation tandemly. two relay processes compete for the same sites, especially under pH‐neutral condition, resulting in suboptimal efficiency selectivity electrosynthesis from . Herein, we constructed Cu 1 ‐Fe dual‐site catalyst by anchoring single on amorphous iron oxide shell nanoscale zero‐valent (nZVI) RR, achieving an impressive removal 94.8 % 99.2 neutral pH concentration 50 mg L −1 −N conditions, greatly surpassing performance nZVI counterpart. This superior can be attributed synergistic effect enhanced adsorption Fe sites strengthened activation single‐atom decreasing energy barrier rate‐determining step *NO‐to‐*NOH. work develops novel fabricating catalysts enhance , presents environmentally sustainable approach treatment.

Language: Английский

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Cu-based catalysts for electrocatalytic nitrate reduction to ammonia: fundamentals and recent advances

EES Catalysis, Journal Year: 2024, Volume and Issue: 2(3), P. 727 - 752

Published: Jan. 1, 2024

This review provides an overview of Cu-based catalysts for electrocatalytic nitrate reduction to ammonia. It encompasses materials, reaction mechanisms, analysis methods and insights into the practical applications economic prospects.

Language: Английский

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