Photo-Fenton degradation of tetracycline over Z-scheme Fe-g-C3N4/Bi2WO6 heterojunctions: Mechanism insight, degradation pathways and DFT calculation

Applied Catalysis B Environment and Energy, Год журнала: 2022, Номер 310, С. 121326 - 121326

Опубликована: Март 16, 2022

Язык: Английский

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Unveiling the Origins of Selective Oxidation in Single-Atom Catalysis via Co–N₄–C Intensified Radical and Nonradical Pathways

Environmental Science & Technology, Год журнала: 2022, Номер 56(16), С. 11635 - 11645

Опубликована: Июль 11, 2022

Single-atom catalysts (SACs)-based peroxymonosulfate (PMS) systems are highly selective to the type of organic pollutants while mechanisms remain ambiguous. In this work, we carried out experimental and theoretical investigations reveal origins selectivity radical nonradical pathways in a designated Co–N4–C/PMS system. Two typical [bisphenol A (BPA) metronidazole (MNZ)] with different molecular structures were employed for comparison. We found that oxidation (SO4•– HO•) electron-transfer pathway (ETP) co-existed Pollutants (e.g., MNZ) high redox potential degraded primarily by free radicals rather than ETP, oxidization low-redox BPA) was dominated ETP at surface region Co–N4–C which overwhelmed contributions homogeneous phase. Intriguingly, could be manipulated PMS loading, simultaneously increased population elevated Co–N4–C-PMS* complexes ETP. Findings from work will unravel mysterious behavior SACs/PMS micropollutants.

Язык: Английский

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Wood Carbon Based Single-Atom Catalyst for Rechargeable Zn–Air Batteries

ACS Energy Letters, Год журнала: 2021, Номер 6(10), С. 3624 - 3633

Опубликована: Сен. 21, 2021

Low-cost and efficient oxygen reduction reaction (ORR)/oxygen evolution (OER) bifunctional electrocatalysts are vital for the applications of rechargeable Zn–air batteries (ZABs). Given high catalytic activity single-atom catalysts (SACs), preparing SACs on a large scale ZABs is desirable but remains challenging. Herein, in situ formation Fe–N–C plate wood-based porous carbon achieved via facile Lewis acid pretreatment carbonization process. FeCl3 cell wall wood not only produces abundant microchannels also successfully introduces atomically dispersed Fe–N active species into hierarchical structure. Such uniformly dispersive structure enhance ORR/OER performance durability. A ZAB using catalyst cathode shows power density (70.2 mW cm–2, at quasi solid state) long-term stability. This work provides new path large-scale preparation high-performance SACs.

Язык: Английский

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Outlook on Single Atom Catalysts for Persulfate-Based Advanced Oxidation

ACS ES&T Engineering, Год журнала: 2022, Номер 2(10), С. 1776 - 1796

Опубликована: Сен. 7, 2022

Single atom catalysts (SACs) have emerged as a promising catalyst material architecture for energy, chemical, and environmental applications. In the past several years, SACs been increasingly explored persulfate-based advanced oxidation processes (AOPs) due to their superior persulfate activation pollutant degradation performance compared benchmark dissolved ion nanoparticle catalysts. However, there still exist uncertainties on mechanism of by SACs, which involves complex interplay sulfate hydroxyl radicals, singlet oxygen, high-valent metal species, and/or mediated electron transfer. Questions also remain how ions molecularly align single site, are converted into reactive what design parameters lead higher efficiency degradation. this critical review, we examine SAC materials employed AOPs discuss they function differently counterparts. We further our discussion current limitations, opportunities, future research needs in (i) filling knowledge gaps mechanisms persulfate-SAC interactions; (ii) augmenting fundamental with theoretical simulation situ characterization techniques; (iii) improving tailored applications; (iv) proactively considering challenges associated engineering practices water matrixes.

Язык: Английский

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Microenvironment modulation of cobalt single-atom catalysts for boosting both radical oxidation and electron-transfer process in Fenton-like system

Applied Catalysis B Environment and Energy, Год журнала: 2023, Номер 329, С. 122558 - 122558

Опубликована: Март 2, 2023

Язык: Английский

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Switching the reaction mechanisms and pollutant degradation routes through active center size-dependent Fenton-like catalysis

Applied Catalysis B Environment and Energy, Год журнала: 2023, Номер 329, С. 122569 - 122569

Опубликована: Март 5, 2023

Язык: Английский

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Coupled Surface-Confinement Effect and Pore Engineering in a Single-Fe-Atom Catalyst for Ultrafast Fenton-like Reaction with High-Valent Iron-Oxo Complex Oxidation

Environmental Science & Technology, Год журнала: 2023, Номер 57(41), С. 15667 - 15679

Опубликована: Окт. 6, 2023

The nanoconfinement effect in Fenton-like reactions shows great potential environmental remediation, but the construction of confinement structure and corresponding mechanism are rarely elucidated systematically. Herein, we proposed a novel peroxymonosulfate (PMS) activation system employing single Fe atom supported on mesoporous N-doped carbon (FeSA-MNC, specific surface area = 1520.9 m2/g), which could accelerate catalytic oxidation process via surface-confinement effect. degradation activity confined was remarkably increased by 34.6 times compared to its analogue unconfined system. generation almost 100% high-valent iron-oxo species identified 18O isotope-labeled experiments, quenching tests, probe methods. density functional theory illustrated that narrows gap between d-band center Fermi level atom, strengthens charge transfer rate at reaction interface reduces free energy barrier for PMS activation. exhibited excellent pollutant efficiency, robust resistance coexisting matter, adaptation wide pH range (3.0-11.0) various temperature environments (5-40 °C). Finally, FeSA-MNC/PMS achieve sulfamethoxazole removal without significant performance decline after 10,000-bed volumes. This work provides insights into chemistry guides design superior systems remediation.

Язык: Английский

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Iron active sites encapsulated in N-doped graphite for efficiently selective degradation of emerging contaminants via peroxymonosulfate (PMS) activation: Inherent roles of adsorption and electron-transfer dominated nonradical mechanisms

Chemical Engineering Journal, Год журнала: 2022, Номер 444, С. 136623 - 136623

Опубликована: Апрель 27, 2022

Язык: Английский

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Nitrogen-doped carbon-based single-atom Fe catalysts: Synthesis, properties, and applications in advanced oxidation processes

Coordination Chemistry Reviews, Год журнала: 2022, Номер 475, С. 214874 - 214874

Опубликована: Окт. 15, 2022

Язык: Английский

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Facilely Tuning the First-Shell Coordination Microenvironment in Iron Single-Atom for Fenton-like Chemistry toward Highly Efficient Wastewater Purification

Environmental Science & Technology, Год журнала: 2023, Номер 57(37), С. 14046 - 14057

Опубликована: Сен. 2, 2023

Precisely identifying the atomic structures in single-atom sites and establishing authentic structure-activity relationships for catalyst (SAC) coordination are significant challenges. Here, theoretical calculations first predicted underlying catalytic activity of Fe-NxC4-x with diverse first-shell environments. Substituting N C to coordinate central Fe atom induces an inferior Fenton-like efficiency. Then, Fe-SACs carrying three configurations (Fe-N2C2, Fe-N3C1, Fe-N4) fabricate facilely demonstrate that optimized environments significantly promote activity. Specifically, reaction rate constant increases from 0.064 0.318 min-1 as number Fe-N 2 4, slightly influencing nonradical mechanism dominated by 1O2. In-depth unveil modulated Fe-N2C2 Fe-N4 optimize d-band electronic regulate binding strength peroxymonosulfate on sites, resulting a reduced energy barrier enhanced The stability actual hospital sewage treatment capacity also showed strong dependency. This strategy local engineering offers vivid example modulating SACs well-regulated environments, ultimately maximizing their

Язык: Английский

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