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

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(31)

Опубликована: Май 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.

Язык: Английский

---

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

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Сен. 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.

Язык: Английский

---

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

Angewandte Chemie International Edition, Год журнала: 2024, Номер 64(1)

Опубликована: Сен. 4, 2024

Electrocatalytic nitrate reduction reaction (NO

Язык: Английский

---

Atomic Cobalt Metal Centers with Asymmetric N/B‐Coordination for Promoting Oxygen Reduction Reaction

Advanced Functional Materials, Год журнала: 2024, Номер 34(48)

Опубликована: Июль 5, 2024

Abstract Cobalt single atom catalysts (SACs) have exhibited promising performance in both the oxygen reduction reaction (ORR) and evolution (OER), positioning them as potential dual‐functional for Zn‐air battery. However, long‐standing challenge lies achieving satisfactory dual‐functionality stability of these SACs. In this study, to optimize 4e ‒ ORR performance, boron (B) atoms are employed with low electronegativity regulate structure Co–N–C catalytic center. This resulted formation an asymmetrically coordinated Co metal center catalyst (Co‐N 3 B). Compared Co‐N 4 , B lower free energy stronger adsorption toward * O species, effectively suppressing 2e pathway at cobalt site preventing corrosion induced by hydrogen peroxide (H 2 ) reactions, thereby enhancing stability. situ attenuated total reflectance surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRAS) further validated excellent interaction between active centers intermediates. Furthermore, self‐made rechargeable zinc‐air battery demonstrated remarkable discharge peak power density (≈253 mW cm ‒2 ), (≈819 mAh g ‒1 cyclic exceeding 110 h. study provides new insights into constructing atomic‐level precision offers strong references practical applications storage convension electrocatalysts.

Язык: Английский

---

Interfacial Water Regulation for Nitrate Electroreduction to Ammonia at Ultralow Overpotentials

Advanced Materials, Год журнала: 2025, Номер unknown

Опубликована: Янв. 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.

Язык: Английский

---

Atomically Dispersed Co–P Moieties via Direct Thermal Exfoliation for Alkaline Hydrogen Electrosynthesis

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 25, 2025

The development of highly active and stable cathodes in alkaline solutions is crucial for promoting the commercialization anion exchange membrane (AEM) electrolyzers, yet it remains a significant challenge. Herein, we synthesized atomically dispersed CoP4 moieties (CoP4–SSC) immobilized on ultrathin carbon nanosheets via phosphidation exfoliation strategy at medium temperature. thermodynamic formation process Co–P was elucidated using X-ray absorption spectroscopy (XAS) theoretical calculations. Remarkably, resulting CoP4–SSC electrocatalyst exhibited outstanding activity hydrogen evolution, with low overpotential 52 mV 10 mA cm–2 turnover frequency up to 23.83 s–1. Moreover, AEM electrolyzer fabricated achieved current density 1 A under an applied voltage only 1.94 V, showing negligible degradation after 500 h continuous electrocatalysis. series operando characterizations functional theory calculations revealed that formed nanointerface [P-*H···H2O*-Co], which facilitates water dissociation during Volmer–Heyrovsky pathway.

Язык: Английский

---

Enhancing Electrocatalytic Activity Through Targeted Local Electrolyte Micro‐Environment

Advanced Functional Materials, Год журнала: 2025, Номер unknown

Опубликована: Янв. 10, 2025

Abstract The local electrolyte micro‐environment surrounding the catalyst reaction center, including critical factors such as pH, reactant concentration, and electric field, plays a decisive role in electrocatalytic reactions water splitting. Recently, this topic has garnered significant attention due to its potential significantly enhance catalytic performance. While various strategies optimize processes have been explored, deliberate control over fundamental principles guiding these adjustments remain their early stages of development. This review provides comprehensive examination key efforts aimed at designing tailoring localized micro‐environments improve It discusses advances micro‐environmental design, methodologies for evaluating shifts, mechanistic insights driving developments. Additionally, highlights existing challenges prospective industrial applications strategies. By offering detailed analysis recent developments, aims equip researchers with practical knowledge on controlling micro‐environments, thereby accelerating progress toward real‐world processes.

Язык: Английский

---

Balancing Hydrogen Evolution and Hydrogenation Reaction via Facet Engineering for Efficient Conversion of Nitrate to Ammonia in Actual Wastewater

Angewandte Chemie International Edition, Год журнала: 2025, Номер unknown

Опубликована: Март 11, 2025

Abstract Due to the competitive relationship between nitrate reduction reaction (NO 3 − RR) and hydrogen evolution (HER), conventional approach improve Faradaic efficiency is select a catalyst without HER activity. Nevertheless, such strategy not only limits application of catalysts in NO RR, but also causes insufficient source, thereby sacrificing ammonia yield rate. We believe that should be excluded from hydrogenation reduction. Herein, taking traditional water electrolysis material Co O 4 as model system, we reveal oxygen vacancies on crystal facet can greatly promote dissociation capture intermediate for successfully shifting pathway hydrogenation. Beyond development, construct hybrid reactor achieve an recovery rate 1216.8 g‐N m −2 d −1 nuclear industry wastewater with ultra‐high concentration. This study breaks through limitation which provides significant insight into designing mechanism.

Язык: Английский

---

Subnanometric Nickel Phosphide Heteroclusters with Highly Active Ni^δ+–P^δ− Pairs for Nitrate Reduction toward Ammonia

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Март 26, 2025

The development of efficient electrocatalysts for the neutral nitrate reduction reaction (NO3–RR) toward ammonia (NH3) is essential to address environmental issues caused by NO3– but remains considerably challenging owing sluggish kinetics NO3–RR in media. Herein, we report subnanometric heteroclusters with strongly coupled nickel–phosphorus (Ni–P) dual-active sites as boost NO3–RR. Experimental and theoretical results reveal that feature Ni–P promotes electron transfer from Ni P, generating Niδ+–Pδ− active pairs, which Niδ+ species are highly Pδ− tunes interfacial water hydrogen bonding network promote dissociation step accelerate proton during Consequently, NO3–RR, exhibit a large NH3 yield rate 0.61 mmol h–1 cm–2 at −0.8 V versus reversible electrode, 2.8- 3.3-fold larger than those on nanoparticles clusters, respectively, generated exists NH4+ electrolytes. This study offers an approach boosting electrocatalytic reactions multiple intermediates designing sites.

Язык: Английский

---

Boosting nitrate electroreduction to ammonia on atomic Ru-Co pair sites in hollow spinels

Applied Catalysis B Environment and Energy, Год журнала: 2024, Номер 358, С. 124387 - 124387

Опубликована: Июль 9, 2024

Язык: Английский

---