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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Promoting ZIF-8-Derived Fe–N–C Oxygen Reduction Catalysts via Zr Doping in Proton Exchange Membrane Fuel Cells: Durability and Activity Enhancements

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(7), P. 4221 - 4230

Published: March 13, 2023

The atomically dispersed iron site and nitrogen co-doped carbon catalysts (Fe–N–C) have demonstrated promising performance in replacing Pt toward the oxygen reduction reaction (ORR) acids for proton exchange membrane fuel cells. However, insufficient durability of Fe–N–C prohibitively hinders their practical applications. Herein, we report that co-doping Zr Fe dual metal sites into a ZIF-8-derived mesoporous exhibited significantly improved ORR. Especially, electrode assembly from ORR cathode catalyst only lost 25% voltage after 20 h continuous operation at constant current density. After an extended test up to 100 h, Zr-doped retained 40% its initial performance, superior without doping with more than 70% activity loss h. also showed activity, achieving maximum power density 0.72 W cm–2 under H2/air conditions. Extensive experimental characterization functional theory calculations suggested promoted catalytic stability are due formation Zr-based active enhanced acidic tolerance individual sites. Also, could suppress H2O2 other free radicals, thus mitigating degradation. possible Fe/Zr dual-metal sites, i.e., N2(N)–Fe–N2–Zr–N2(O2), likely intrinsic relative conventional FeNx

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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Homonuclear dual-atom catalysts embedded on N-doped graphene for highly efficient nitrate reduction to ammonia: From theoretical prediction to experimental validation

Applied Catalysis B Environment and Energy, Journal Year: 2023, Volume and Issue: 339, P. 123156 - 123156

Published: Aug. 7, 2023

Language: Английский

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Electron-deficient cobalt nanocrystals for promoted nitrate electrocatalytic reduction to synthesize ammonia

Nano Energy, Journal Year: 2023, Volume and Issue: 117, P. 108901 - 108901

Published: Sept. 13, 2023

Language: Английский

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NH₃ Electrosynthesis from N₂ Molecules: Progresses, Challenges, and Future Perspectives

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(10), P. 6409 - 6421

Published: Feb. 27, 2024

Green ammonia (NH3), made by using renewable electricity to split nearly limitless nitrogen (N2) molecules, is a vital platform molecule and an ideal fuel drive the sustainable development of human society without carbon dioxide emission. The NH3 electrosynthesis field currently faces dilemma low yield rate efficiency; however, decoupling overlapping issues this area providing guidelines for its directions are not trivial because it involves complex reaction process multidisciplinary entries (for example, electrochemistry, catalysis, interfaces, processes, etc.). In Perspective, we introduce classification scheme based on process, namely, direct (N2 reduction reaction) indirect (Li-mediated/plasma-enabled electrosynthesis). This categorization allows us finely decouple complicated pathways identify specific rate-determining steps/bottleneck each synthesis approach such as N2 activation, H2 evolution side reaction, solid-electrolyte interphase engineering, plasma etc. We then present detailed overview latest progresses solving these core in terms whole electrochemical system covering electrocatalysts, electrodes, electrolytes, electrolyzers, Finally, discuss research focuses promising strategies future with multiscale perspective atomistic mechanisms, nanoscale microscale electrodes/interfaces, macroscale electrolyzers/processes. It expected that Perspective will provide readers in-depth understanding bottleneck insightful guidance designing efficient systems.

Language: Английский

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Progress in Single/Multi Atoms and 2D‐Nanomaterials for Electro/Photocatalytic Nitrogen Reduction: Experimental, Computational and Machine Leaning Developments

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

Published: Feb. 11, 2024

Abstract The conversion of atmospheric nitrogen (N 2 ) into ammonia (NH 3 ), known as fixation, plays a crucial role in sustaining life on Earth, facing innovation with electrocatalytic and photocatalytic methods. These approaches promise gentler conversions from to ammonia, diverging the energy‐intensive Haber‐Bosch process, which requires complex plant infrastructure. Vitality lies eco‐friendly, cost‐effective, energy‐efficient pathways. challenge is that electrocatalysts photocatalysts for reduction have shown low Faraday efficiency, hampered by hydrogen evolution. This work delves recent strides electro/photo‐catalytic fixation/reduction, deciphering mechanisms, catalysts, prospects. By unveiling core principles steering these processes, it dissects efficiency drivers. Experimental theoretical studies, ranging density functional calculations/simulations machine learning‐based catalyst screening, mark path toward highly efficient including single/multi‐atom catalysts embedded 2D materials. journey explores diverse assessing their performance, spotlighting emerging nanomaterials, heterostructures, co‐catalyst techniques. Perspectives future directions potential applications fixation/reduction are offered, emphasizing sustainable management implications global agriculture environmental sustainability.

Language: Английский

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Selective Electrocatalytic Conversion of Nitric Oxide to High Value‐Added Chemicals

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(18)

Published: Jan. 25, 2024

The artificial disturbance in the nitrogen cycle has necessitated an urgent need for nitric oxide (NO) removal. Electrochemical technologies NO conversion have gained increasing attention recent years. This comprehensive review presents advancements selective electrocatalytic of to high value-added chemicals, with specific emphasis on catalyst design, electrolyte composition, mass diffusion, and adsorption energies key intermediate species. Furthermore, explores synergistic electrochemical co-electrolysis carbon source molecules, enabling synthesis a range valuable chemicals C─N bonds. It also provides in-depth insights into intricate reaction pathways underlying mechanisms, offering perspectives challenges prospects electrolysis. By advancing comprehension fostering awareness balance, this contributes development efficient sustainable systems from NO.

Language: Английский

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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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Hierarchically Ordered Pore Engineering of Metal–Organic Framework‐Based Materials for Electrocatalysis

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(27)

Published: April 17, 2024

Abstract Ordered pore engineering that embeds uniform pores with periodic alignment in electrocatalysts opens up a new avenue for achieving further performance promotion. Hierarchically ordered porous metal–organic frameworks (HOP‐MOFs) possessing multilevel distribution are the promising precursors exploration of electrocatalysts, while scalable acquisition HOP‐MOFs editable components and adjustable size regimes is critical. This review presents recent progress on hierarchically MOF‐based materials enhanced electrocatalysis. The synthetic strategies different regimes, including self‐assembly guided by reticular chemistry, surfactant, nanoemulsion, nanocasting, first introduced. Then applications as exploring summarized, selecting representatives to highlight boosted performance. Especially, intensification molecule ion transport integrated optimized electron transfer site exposure over derivatives emphasized clarify directional integration effect endowed engineering. Finally, remaining scientific challenges an outlook this field proposed. It hoped will guide nanocatalysts boosting catalytic promoting practical applications.

Language: Английский

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