Linear Adsorption Enables NO Selective Electroreduction to Hydroxylamine on Single Co Sites

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(27)

Опубликована: Май 2, 2023

Hydroxylamine (NH2 OH), a vital industrial feedstock, is presently synthesized under harsh conditions with serious environmental and energy concerns. Electrocatalytic nitric oxide (NO) reduction attractive for the production of hydroxylamine ambient conditions. However, selectivity limited by competitive reaction ammonia production. Herein, we regulate adsorption configuration NO adjusting atomic structure catalysts to control product selectivity. Co single-atom show state-of-the-art NH2 OH from electroreduction neutral (FE NH2OH${{_{{\rm NH}{_{2}}{\rm OH}}}}$ : 81.3 %), while nanoparticles are inclined generate NH3${{_{{\rm NH}{_{3}}}}}$ 92.3 %). A series in situ characterizations theoretical simulations unveil that linear on isolated sites enables formation bridge adjacent induces ammonia.

Язык: Английский

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Electrochemical Potential-Driven Shift of Frontier Orbitals in M–N–C Single-Atom Catalysts Leading to Inverted Adsorption Energies

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(46), С. 25264 - 25273

Опубликована: Ноя. 8, 2023

Electronic structure is essential to understanding the catalytic mechanism of metal single-atom catalysts (SACs), especially under electrochemical conditions. This study delves into nuanced modulation "frontier orbitals" in SACs on nitrogen-doped graphene (N-C) substrates by potentials. We observe shifts Fermi level and changes d-orbital occupation with alterations potentials, emphasizing a synergy between discretized atomic orbitals metals continuous bands N-C based environment. Using O2 CO2 as model adsorbates, we highlight direct consequences these adsorption energies, unveiling an intriguing inversion energies Co/N-C SAC negative Such insights are attributed role dxz dz2 orbitals, pivotal for stabilizing π* O2. Through this exploration, our work offers interplay electronic structures behaviors SACs, paving way enhanced catalyst design strategies processes.

Язык: Английский

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Single‐Atom Catalysts for H₂O₂ Electrosynthesis via Two‐Electron Oxygen Reduction Reaction

Advanced Functional Materials, Год журнала: 2023, Номер 33(15)

Опубликована: Фев. 28, 2023

Abstract Oxygen reduction reaction via the two‐electron route (2e − ORR) provides a green method for direct production of hydrogen peroxide (H 2 O ) along with in situ utilization. The effective catalysts high ORR activity, 2e selectivity, and stability are essential application this technology. Single‐atom (SACs) have attracted intensively attention H electrosynthesis owing to unique geometric electronic configurations. In review, mechanism theoretical predictions over SACs first introduced. Then, recent advances various documented. And correlation between central atom, coordination atoms, environment corresponding electrocatalytic performance including emphatically analyzed summarized. Finally, major challenges opportunities regarding future design pointed out.

Язык: Английский

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Challenges and Perspectives of Single-Atom-Based Catalysts for Electrochemical Reactions

JACS Au, Год журнала: 2023, Номер 3(3), С. 736 - 755

Опубликована: Фев. 16, 2023

Single-atom catalysts (SACs) are emerging as the most promising for various electrochemical reactions. The isolated dispersion of metal atoms enables high density active sites, and simplified structure makes them ideal model systems to study structure–performance relationships. However, activity SACs is still insufficient, stability usually inferior but has received little attention, hindering their practical applications in real devices. Moreover, catalytic mechanism on a single site unclear, leading development rely trial-and-error experiments. How can one break current bottleneck sites density? further increase activity/stability sites? In this Perspective, we discuss underlying reasons challenges identify precisely controlled synthesis involving designed precursors innovative heat-treatment techniques key high-performance SACs. addition, advanced operando characterizations theoretical simulations essential uncovering true electrocatalytic an site. Finally, future directions that may arise breakthroughs discussed.

Язык: Английский

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Dithiine-linked metalphthalocyanine framework with undulated layers for highly efficient and stable H2O2 electroproduction

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Янв. 23, 2024

Realization of stable and industrial-level H

Язык: Английский

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Advances on Axial Coordination Design of Single-Atom Catalysts for Energy Electrocatalysis: A Review

Nano-Micro Letters, Год журнала: 2023, Номер 15(1)

Опубликована: Окт. 13, 2023

Abstract Single-atom catalysts (SACs) have garnered increasingly growing attention in renewable energy scenarios, especially electrocatalysis due to their unique high efficiency of atom utilization and flexible electronic structure adjustability. The intensive efforts towards the rational design synthesis SACs with versatile local configurations significantly accelerated development efficient sustainable electrocatalysts for a wide range electrochemical applications. As an emergent coordination avenue, intentionally breaking planar symmetry by adding ligands axial direction metal single atoms offers novel approach tuning both geometric structures, thereby enhancing electrocatalytic performance at active sites. In this review, we briefly outline burgeoning research topic axially coordinated provide comprehensive summary recent advances synthetic strategies Besides, challenges outlooks field also been emphasized. present review provides in-depth understanding SACs, which could bring new perspectives solutions fine regulation structures catering high-performing electrocatalysis.

Язык: Английский

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Enhancing H₂O₂ Electrosynthesis at Industrial-Relevant Current in Acidic Media on Diatomic Cobalt Sites

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(13), С. 9434 - 9443

Опубликована: Март 20, 2024

Electrocatalytic synthesis of hydrogen peroxide (H2O2) in acidic media is an efficient and eco-friendly approach to produce inherently stable H2O2, but limited by the lack selective catalysts under industrial-relevant current densities. Herein, we report a diatomic cobalt catalyst for two-electron oxygen reduction efficiently H2O2 at 50–400 mA cm–2 acid. Electrode kinetics study shows >95% selectivity on sites. In flow cell device, record-high production rate 11.72 mol gcat–1 h–1 exceptional long-term stability (100 h) are realized high situ spectroscopic studies theoretical calculations reveal that introducing second metal into coordination sphere site can optimize binding strength key intermediates due downshifted d-band center cobalt. We also demonstrate feasibility processing municipal plastic wastes through decentralized production.

Язык: Английский

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Review and perspectives on carbon-based electrocatalysts for the production of H₂O₂via two-electron oxygen reduction

Green Chemistry, Год журнала: 2023, Номер 25(23), С. 9501 - 9542

Опубликована: Янв. 1, 2023

As a versatile and environmentally friendly chemical, hydrogen peroxide (H 2 O ) is in high demand.

Язык: Английский

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Nanoconfinement steers nonradical pathway transition in single atom fenton-like catalysis for improving oxidant utilization

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Июнь 22, 2024

Abstract The introduction of single-atom catalysts (SACs) into Fenton-like oxidation promises ultrafast water pollutant elimination, but the limited access to pollutants and oxidant by surface catalytic sites intensive consumption still severely restrict decontamination performance. While nanoconfinement SACs allows drastically enhanced reaction kinetics, detailed regulatory mechanisms remain elusive. Here, we unveil that, apart from local enrichment reactants, pathway shift is also an important cause for reactivity enhancement nanoconfined SACs. electronic structure cobalt site altered confining it within nanopores mesostructured silica particles, which triggers a fundamental transition singlet oxygen electron transfer 4-chlorophenol oxidation. changed accelerated interfacial mass render system up 34.7-fold higher degradation rate raised peroxymonosulfate utilization efficiency (from 61.8% 96.6%) relative unconfined control. It demonstrates superior other electron-rich phenolic compounds, good environment robustness, high stability treating real lake water. Our findings deepen knowledge catalysis may inspire innovations in low-carbon purification technologies heterogeneous applications.

Язык: Английский

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p-Block-metal bismuth-based electrocatalysts featuring tunable selectivity for high-performance oxygen reduction reaction

Joule, Год журнала: 2023, Номер 7(5), С. 1003 - 1015

Опубликована: Май 1, 2023

Язык: Английский

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