Origins of Electron-Transfer Regime in Persulfate-Based Nonradical Oxidation Processes

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 56(1), P. 78 - 97

Published: Dec. 21, 2021

Persulfate-based nonradical oxidation processes (PS-NOPs) are appealing in wastewater purification due to their high efficiency and selectivity for removing trace organic contaminants complicated water matrices. In this review, we showcased the recent progresses of state-of-the-art strategies electron-transfer regimes PS-NOPs, including design metal metal-free heterogeneous catalysts, situ/operando characterization/analytical techniques, insights into origins mechanisms. a typical process (ETP), persulfate is activated by catalyst form surface complexes, which directly or indirectly interact with target pollutants finalize oxidation. We discussed different analytical techniques on fundamentals tactics accurate analysis ETP. Moreover, demonstrated challenges proposed future research ETP-based systems, such as computation-enabled molecular-level investigations, rational real-scenario applications environment. Overall, review dedicates sharpening understanding ETP PS-NOPs presenting promising remediation technology green chemistry.

Language: 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, Journal Year: 2022, Volume and Issue: 56(16), P. 11635 - 11645

Published: July 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.

Language: Английский

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Merits and Limitations of Radical vs. Nonradical Pathways in Persulfate-Based Advanced Oxidation Processes

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(33), P. 12153 - 12179

Published: Aug. 3, 2023

Urbanization and industrialization have exerted significant adverse effects on water quality, resulting in a growing need for reliable eco-friendly treatment technologies. Persulfate (PS)-based advanced oxidation processes (AOPs) are emerging as viable technologies to treat challenging industrial wastewaters or remediate groundwater impacted by hazardous wastes. While the generated reactive species can degrade variety of priority organic contaminants through radical nonradical pathways, there is lack systematic in-depth comparison these pathways practical implementation different scenarios. Our comparative analysis reaction rate constants vs. indicates that radical-based AOPs may achieve high removal efficiency with relatively short contact time. Nonradical feature advantages minimal matrix interference complex wastewater treatments. (e.g., singlet oxygen, high-valent metals, surface activated PS) preferentially react bearing electron-donating groups, allowing enhancement degradation known target contaminants. For byproduct formation, analytical limitations computational chemistry applications also considered. Finally, we propose holistically estimated electrical energy per order (EE/O) parameter show significantly higher requirements pathways. Overall, critical comparisons help prioritize basic research PS-based inform merits system-specific applications.

Language: Английский

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Generating dual-active species by triple-atom sites through peroxymonosulfate activation for treating micropollutants in complex water

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(13)

Published: March 23, 2023

The peroxymonosulfate (PMS)-triggered radical and nonradical active species can synergistically guarantee selectively removing micropollutants in complex wastewater; however, realizing this on heterogeneous metal-based catalysts with single sites remains challenging due to insufficient electron cycle. Herein, we design asymmetric Co-O-Bi triple-atom Co-doped Bi2O2CO3 facilitate PMS oxidation reduction simultaneously by enhancing the transfer between sites. We propose that result an density increase Bi decrease Co sites, thereby undergoes a reaction generate SO4•- •OH at site 1O2 site. suggest synergistic effect of SO4•-, •OH, enables efficient removal mineralization without interference from organic inorganic compounds under environmental background. As result, achieves almost 99.3% sulfamethoxazole degradation 3 min k-value as high 82.95 min-1 M-1, which is superior existing reported so far. This work provides structural regulation approach control catalytic function, will guide rational Fenton-like catalysts.

Language: Английский

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Cobalt Single Atoms Anchored on Oxygen‐Doped Tubular Carbon Nitride for Efficient Peroxymonosulfate Activation: Simultaneous Coordination Structure and Morphology Modulation

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(29)

Published: May 6, 2022

Abstract Simultaneous regulation of the coordination environment single‐atom catalysts (SACs) and engineering architectures with efficient exposed active sites are strategies for boosting peroxymonosulfate (PMS) activation. We isolated cobalt atoms dual nitrogen oxygen (Co−N 3 O 1 ) on oxygen‐doped tubular carbon nitride (TCN) by pyrolyzing a hydrogen‐bonded cyanuric acid melamine–cobalt acetate precursor. The theoretically constructed Co−N moiety TCN exhibited an impressive mass activity 7.61×10 5 min −1 mol high 2 selectivity. Theoretical calculations revealed that single occupied environment, PMS adsorption was promoted energy barriers reduced key *O intermediate produced . were attached to widely used poly(vinylidene fluoride) microfiltration membrane deliver antibiotic wastewater treatment system 97.5 % ciprofloxacin rejection over 10 hours, thereby revealing suitability industrial applications.

Language: Английский

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Interface Engineering of Co(OH)₂ Nanosheets Growing on the KNbO₃ Perovskite Based on Electronic Structure Modulation for Enhanced Peroxymonosulfate Activation

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(8), P. 5200 - 5212

Published: April 8, 2022

Material-enhanced heterogonous peroxymonosulfate (PMS) activation on emerging organic pollutant degradation has attracted intensive attention, and a challenge is the electron transfer efficiency from material to PMS for radical production. Herein, an interface architecture of Co(OH)2 nanosheets growing KNbO3 perovskite [Co(OH)2/KNbO3] was developed, which showed high catalytic activity in activation. A reaction rate constant (k1) 0.631 min-1 complete removal pazufloxacin within 5 min were achieved. X-ray photoelectron spectroscopy, absorption near edge structure spectra, density functional theory (DFT) calculations revealed successful construction modulated electronic Co(OH)2/KNbO3, resulting hole accumulation KNbO3. Bader topological analysis charge distribution further indicates that occupations Co-3d O-2p orbitals Co(OH)2/KNbO3 are pushed above Fermi level form antibonding states (σ*), leading chemisorption affinity PMS. In addition, more reactive Co(II) with closer d-band center results higher lower decomposition energy SO4•-. Moreover, sites SO4•- attack precisely identified based DFT calculation Fukui index. The pathways proceeded as decarboxylation, nitroheterocyclic ring opening reaction, defluorination, hydroxylation. This work can provide potential route developing advanced catalysts manipulation enhanced Fenton-like such

Language: Английский

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Toward Selective Oxidation of Contaminants in Aqueous Systems

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(21), P. 14494 - 14514

Published: Oct. 20, 2021

The presence of diverse pollutants in water has been threating human health and aquatic ecosystems on a global scale. For more than century, chemical oxidation using strongly oxidizing species was one the most effective technologies to destruct ensure safe clean supply. However, removal increasing amount with higher structural complexity, especially emerging micropollutants trace concentrations complicated matrix, requires excessive dosage oxidant and/or energy input, resulting low cost-effectiveness possible secondary pollution. Consequently, it is practical significance but scientifically challenging achieve selective interest for decontamination. Currently, there are variety examples concerning aqueous systems. systematic understanding relationship between origin selectivity its applicable treatment scenarios, as well rational design catalyst catalytic oxidation, still lacking. In this critical review, we summarize state-of-the-art strategies decontamination probe origins selectivity, that is, from reactivity either oxidants or target pollutants, arising accessibility via adsorption size exclusion, due interfacial electron transfer process enzymatic oxidation. Finally, challenges perspectives briefly outlined stimulate future discussion decontamination, particularly toward application real scenarios.

Language: Английский

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Rational Regulation of Co–N–C Coordination for High-Efficiency Generation of ¹O₂ toward Nearly 100% Selective Degradation of Organic Pollutants

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(12), P. 8833 - 8843

Published: May 26, 2022

Single oxygen-based advanced oxidation processes (1O2-AOPs) exhibit great prospects in selective degradation of organic pollutants. However, efficient production 1O2 via tailored design catalysts to achieve contaminants remains challenging. Herein, we develop a simple strategy regulate the components and coordination Co–N–C at atomic level by adjusting Zn/Co ratio bimetallic zeolitic imidazolate frameworks (ZnxCo1-ZIFs). Zn4Co1–C demonstrates 98% removal phenol mixed phenol/benzoic acid (phenol/BA) solutions. Density functional theory calculations experiments reveal that more active CoN4 sites are generated Zn4Co1–C, which beneficial peroxymonosulfate activation generate 1O2. Furthermore, correlation between origin selectivity well-defined is systematically investigated electron paramagnetic resonance test quenching experiments. This work may provide novel insights into target pollutants complicated water matrix.

Language: Английский

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Nitrogen defects/boron dopants engineered tubular carbon nitride for efficient tetracycline hydrochloride photodegradation and hydrogen evolution

Applied Catalysis B Environment and Energy, Journal Year: 2021, Volume and Issue: 303, P. 120932 - 120932

Published: Nov. 15, 2021

Language: Английский

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Functional Carbon Nitride Materials in Photo‐Fenton‐Like Catalysis for Environmental Remediation

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(24)

Published: May 12, 2022

Abstract Among various advanced oxidation processes, coupled photocatalysis and heterogeneous Fenton‐like catalysis (known as photo‐Fenton‐like catalysis) to generate highly reactive species for environmental remediation has attracted wide interests. As an emerging metal‐free photocatalyst, graphitic carbon nitride (g‐C 3 N 4 , CN) been recently recognized a promising candidate catalyze robustly reactions wastewater remediation. This review summarizes recent progress in fabricating types of CN‐based catalysts the reaction process. Innovative engineering strategies on CN matrix are outlined, ranging from morphology control, defect engineering, nonmetal atom doping, organic molecule doping modification by metal‐containing species. The catalytic activities loaded with auxiliary sub‐nanoscale (e.g., quantum dots, organometallic molecules, metal cations, single metals) nanoscale metal‐based materials critically evaluated. Hybridization bandgap‐matching semiconductors construction type‐II Z‐scheme heterojunctions also examined. critical factors morphology, dimensionality, light absorption, charge excitation/migration, sites, H 2 O generation activation) that determine performance photocatalysts systematically discussed. After examining structure–activity relationship, research perspectives proposed further development toward more efficient their application practical water treatment.

Language: Английский

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