Ultrahigh Peroxymonosulfate Utilization Efficiency over CuO Nanosheets via Heterogeneous Cu(III) Formation and Preferential Electron Transfer during Degradation of Phenols

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 56(12), P. 8984 - 8992

Published: May 31, 2022

In persulfate activation by copper-based catalysts, high-valent copper (Cu(III)) is an overlooked reactive intermediate that contributes to efficient utilization and organic pollutant removal. However, the mechanisms underlying heterogeneous enhanced are not fully understood. Here, oxide (CuO) nanosheets (synthesized with a facile precipitation method) exhibited high catalytic activity for peroxymonosulfate (PMS) 100% 4-chlorophenol (4-CP) degradation within 3 min. Evidence critical role of surface-associated Cu(III) on PMS 4-CP over wide pH range (pH 3-10) was obtained using in situ Raman spectroscopy, electron paramagnetic resonance, quenching tests. directly oxidized other phenolic pollutants, rate constants inversely proportional their ionization potentials. preferentially oxidizes rather than react two molecules generate one molecule 1O2, thus minimizing this less pathway. Accordingly, much higher efficiency (77% electrons accepted ascribed mineralization) CuO/PMS radical pathway-dominated Co3O4/PMS system (27%) or 1O2 α-MnO2/PMS (26%). Overall, these results highlight potential benefits via oxidation offer mechanistic insight into ultrahigh

Language: Английский

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Oxygen doping of cobalt-single-atom coordination enhances peroxymonosulfate activation and high-valent cobalt–oxo species formation

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(16)

Published: April 11, 2023

The high-valent cobalt-oxo species (Co(IV)=O) is being increasingly investigated for water purification because of its high redox potential, long half-life, and antiinterference properties. However, generation Co(IV)=O inefficient unsustainable. Here, a cobalt-single-atom catalyst with N/O dual coordination was synthesized by O-doping engineering. O-doped (Co-OCN) greatly activated peroxymonosulfate (PMS) achieved pollutant degradation kinetic constant 73.12 min-1 g-2, which 4.9 times higher than that Co-CN (catalyst without O-doping) those most reported single-atom catalytic PMS systems. Co-OCN/PMS realized dominant oxidation pollutants increasing the steady-state concentration (1.03 × 10-10 M) 5.9 compared Co-CN/PMS. A competitive kinetics calculation showed contribution to micropollutant 97.5% during process. Density functional theory calculations influenced charge density (increased Bader transfer from 0.68 0.85 e), optimized electron distribution Co center d-band -1.14 -1.06 eV), enhanced adsorption energy -2.46 -3.03 eV, lowered barrier key reaction intermediate (*O*H2O) formation 1.12 0.98 eV. Co-OCN fabricated on carbon felt flow-through device, continuous efficient removal micropollutants (degradation efficiency >85% after 36 h operation). This study provides new protocol activation elimination through heteroatom-doping metal-oxo purification.

Language: Английский

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A critical review on correlating active sites, oxidative species and degradation routes with persulfate-based antibiotics oxidation

Water Research, Journal Year: 2023, Volume and Issue: 235, P. 119926 - 119926

Published: March 27, 2023

Language: Английский

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Single-Atom MnN₅ Catalytic Sites Enable Efficient Peroxymonosulfate Activation by Forming Highly Reactive Mn(IV)–Oxo Species

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(10), P. 4266 - 4275

Published: Feb. 27, 2023

Four-nitrogen-coordinated transitional metal (MN4) configurations in single-atom catalysts (SACs) are broadly recognized as the most efficient active sites peroxymonosulfate (PMS)-based advanced oxidation processes. However, SACs with a coordination number higher than four rarely explored, which represents fundamental missed opportunity for chemistry to boost PMS activation and degradation of recalcitrant organic pollutants. We experimentally theoretically demonstrate here that five-nitrogen-coordinated Mn (MnN5) more effectively activate MnN4 sites, by facilitating cleavage O–O bond into high-valent Mn(IV)–oxo species nearly 100% selectivity. The high activity MnN5 was discerned be due formation higher-spin-state N5Mn(IV)═O species, enable two-electron transfer from organics through lower-energy-barrier pathway. Overall, this work demonstrates importance numbers informs design next-generation environmental catalysts.

Language: Английский

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CoN₁O₂ Single‐Atom Catalyst for Efficient Peroxymonosulfate Activation and Selective Cobalt(IV)=O Generation

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(27)

Published: April 26, 2023

High-valent metal-oxo (HVMO) species are powerful non-radical reactive that enhance advanced oxidation processes (AOPs) due to their long half-lives and high selectivity towards recalcitrant water pollutants with electron-donating groups. However, high-valent cobalt-oxo (CoIV =O) generation is challenging in peroxymonosulfate (PMS)-based AOPs because the 3d-orbital occupancy of cobalt would disfavor its binding a terminal oxygen ligand. Herein, we propose strategy construct isolated Co sites unique N1 O2 coordination on Mn3 O4 surface. The asymmetric configuration able accept electrons from 3d-orbital, resulting significant electronic delocalization at for promoted PMS adsorption, dissociation subsequent CoIV =O species. CoN1 /Mn3 exhibits intrinsic activity activation sulfamethoxazole (SMX) degradation, highly outperforming counterpart CoO3 configuration, carbon-based single-atom catalysts CoN4 commercial oxides. effectively oxidize target contaminants via atom transfer produce low-toxicity intermediates. These findings could advance mechanistic understanding molecular level guide rational design efficient environmental catalysts.

Language: Английский

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Fe-Mn oxycarbide anchored on N-doped carbon for enhanced Fenton-like catalysis: Importance of high-valent metal-oxo species and singlet oxygen

Applied Catalysis B Environment and Energy, Journal Year: 2023, Volume and Issue: 340, P. 123204 - 123204

Published: Aug. 22, 2023

Language: Английский

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Generation of Fe^IV=O and its Contribution to Fenton‐Like Reactions on a Single‐Atom Iron−N−C Catalyst

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(10)

Published: Jan. 10, 2023

Generating FeIV =O on single-atom catalysts by Fenton-like reaction has been established for water treatment; however, the generation pathway and oxidation behavior remain obscure. Employing an Fe-N-C catalyst with a typical Fe-N4 moiety to activate peroxymonosulfate (PMS), we demonstrate that generating is mediated Fe-N-C-PMS* complex-a well-recognized nonradical species induction of electron-transfer oxidation-and determined adjacent Fe sites specific Fe1 -Fe1 distance are required. After atoms <4 Å PMS-saturated, formed 4-5 can coordinate FeII -N4 , forming inter-complex enhanced charge transfer produce =O. enables system efficiently oxidize various pollutants in substrate-specific, pH-tolerant, sustainable manner, where its prominent contribution manifests higher one-electron potential.

Language: Английский

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Reducing agents enhanced Fenton-like oxidation (Fe(III)/Peroxydisulfate): Substrate specific reactivity of reactive oxygen species

Water Research, Journal Year: 2022, Volume and Issue: 218, P. 118412 - 118412

Published: April 6, 2022

Language: Английский

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Calcination temperature regulates non-radical pathways of peroxymonosulfate activation via carbon catalysts doped by iron and nitrogen

Chemical Engineering Journal, Journal Year: 2022, Volume and Issue: 451, P. 138468 - 138468

Published: Aug. 4, 2022

Language: Английский

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New insights into the degradation of micro-pollutants in the hydroxylamine enhanced Fe(II)/peracetic acid process: Contribution of reactive species and effects of pH

Journal of Hazardous Materials, Journal Year: 2022, Volume and Issue: 441, P. 129885 - 129885

Published: Aug. 31, 2022

Language: Английский

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