Neglected but Efficient Electron Utilization Driven by Biochar-Coactivated Phenols and Peroxydisulfate: Polyphenol Accumulation Rather than Mineralization

Environmental Science & Technology, Год журнала: 2023, Номер 57(14), С. 5703 - 5713

Опубликована: Март 18, 2023

We report an unrecognized but efficient nonradical mechanism in biochar-activated peroxydisulfate (PDS) systems. Combining a newly developed fluorescence trapper of reactive oxygen species with steady-state concentration calculations, we showed that raising pyrolysis temperatures biochar (BC) from 400 to 800 °C remarkably enhanced trichlorophenol degradation inhibited the catalytic production radicals (SO4•– and •OH) water soil, thereby switching radical-based activation into electron-transfer-dominated pathway (contribution increased 12.9 76.9%). Distinct previously reported PDS* complex-determined oxidation, situ Raman electrochemical results this study demonstrated simultaneous phenols PDS on surface triggers potential difference-driven electron transfer. The formed phenoxy subsequently undergo coupling polymerization reactions generate dimeric oligomeric intermediates, which are eventually accumulated removed. Such unique nonmineralizing oxidation achieved ultrahigh utilization efficiency (ephenols/ePDS) 182%. Through molecular modeling theoretical highlighted critical role graphitic domains rather than redox-active moieties lowering band-gap energy facilitate Our work provides insights outstanding contradictions controversies related inspiration for more oxidant-saving remediation technologies.

Язык: Английский

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Redox Oscillations Activate Thermodynamically Stable Iron Minerals for Enhanced Reactive Oxygen Species Production

Environmental Science & Technology, Год журнала: 2023, Номер 57(23), С. 8628 - 8637

Опубликована: Май 31, 2023

Reactive oxygen species (ROS) play key roles in driving biogeochemical processes. Recent studies have revealed nonphotochemical electron transfer from redox-active substances (e.g., iron minerals) to as a new route for ROS production. Yet, naturally occurring minerals mainly exist thermodynamically stable forms, restraining their potential Here, we report that tide-induced redox oscillations can activate enhanced •OH production intertidal soils (15.8 ± 0.5 μmol/m2) was found be 5.9-fold more efficient than those supratidal soils. Moreover, incubation of under tidal fluctuations dramatically by 4.3-fold. The hydrology triggered alternation between biotic reduction and abiotic oxidation could accelerate the reactive ferrous ions amorphous ferric oxyhydroxides, making into metastable phases (RAMPs) with reduced crystallinity promoting surface electrochemical activities. Those RAMPs displayed activity Investigations nationwide coastal verified ubiquitously Our study demonstrates effective formation hydrological perturbations, which provides insights natural sources.

Язык: Английский

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The generation and transformation mechanisms of reactive oxygen species in the environment and their implications for pollution control processes: a review.

Environmental Research, Год журнала: 2024, Номер 260, С. 119592 - 119592

Опубликована: Июль 14, 2024

Язык: Английский

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Strong Substance Exchange at Paddy Soil-Water Interface Promotes Nonphotochemical Formation of Reactive Oxygen Species in Overlying Water

Environmental Science & Technology, Год журнала: 2024, Номер 58(17), С. 7403 - 7414

Опубликована: Апрель 17, 2024

Photochemically generated reactive oxygen species (ROS) are widespread on the earth's surface under sunlight irradiation. However, nonphotochemical ROS generation in water (e.g., paddy overlying water) has been largely neglected. This work elucidated drivers of and its spatial distribution undisturbed water, by combining imaging technology with situ monitoring. It was found that H2O2 concentrations formed three waters could reach 0.03–16.9 μM, profiles exhibited heterogeneity. The O2 planar-optode indicated redox interfaces were not always at soil–water interface but also possibly layer, depending soil properties. facilitated a rapid turnover reducing oxidizing substances, creating an ideal environment for ROS. Additionally, electron-donating capacities increased 4.5–8.4 times compared to top layers. Importantly, field investigation results confirmed sustainable •OH through pathways constituted significant proportion total daily production (>50%), suggesting comparable or even greater role than photochemical generation. In summary, process reported this study greatly enhances understanding natural processes soils.

Язык: Английский

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Soil carbon and nitrogen cycles driven by iron redox: A review

The Science of The Total Environment, Год журнала: 2024, Номер 918, С. 170660 - 170660

Опубликована: Фев. 6, 2024

Язык: Английский

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Seasonal and Spatial Fluctuations of Reactive Oxygen Species in Riparian Soils and Their Contributions on Organic Carbon Mineralization

Environmental Science & Technology, Год журнала: 2024, Номер 58(16), С. 7066 - 7077

Опубликована: Апрель 10, 2024

Reactive oxygen species (ROS) are ubiquitous in the natural environment and play a pivotal role biogeochemical processes. However, spatiotemporal distribution production mechanisms of ROS riparian soil remain unknown. Herein, we performed uninterrupted monitoring to investigate variation at different sites Weihe River zone throughout year. Fluorescence imaging quantitative analysis clearly showed soils. The concentration superoxide (O

Язык: Английский

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Biochar-derived persistent free radicals and reactive oxygen species reduce the potential of biochar to mitigate soil N2O emissions by inhibiting nosZ

Soil Biology and Biochemistry, Год журнала: 2023, Номер 178, С. 108970 - 108970

Опубликована: Янв. 31, 2023

Язык: Английский

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Reactive oxygen species affect the potential for mineralization processes in permeable intertidal flats

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Фев. 20, 2023

Intertidal permeable sediments are crucial sites of organic matter remineralization. These likely have a large capacity to produce reactive oxygen species (ROS) because shifting oxic-anoxic interfaces and intense iron-sulfur cycling. Here, we show that high concentrations the ROS hydrogen peroxide present in intertidal using microsensors, chemiluminescent analysis on extracted porewater. We furthermore investigate effect potential rates microbial degradation processes surface after transient oxygenation, slurries transitioned from oxic anoxic conditions. Enzymatic removal strongly increases aerobic respiration, sulfate reduction accumulation. conclude formed sediments, subsequently moderate mineralization process rates. Although is completely inhibited period, it resumes immediately upon anoxia. This study demonstrates strong effects oxygenation biogeochemistry sediments.

Язык: Английский

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Dynamic Production of Hydroxyl Radicals during the Flooding–Drainage Process of Paddy Soil: An In Situ Column Study

Environmental Science & Technology, Год журнала: 2023, Номер 57(43), С. 16340 - 16347

Опубликована: Окт. 19, 2023

Frequent cycles of flooding and drainage in paddy soils lead to the reductive dissolution iron (Fe) minerals reoxidation Fe(II) species, all while generating a robust consistent output reactive oxygen species (ROS). In this study, we present comprehensive assessment temporal spatial variations Fe ROS during flooding-drainage process representative soil. Our laboratory column experiments showed that decrease dissolved O2 concentration led rapid reduction below water-soil interface, aqueous was transformed into solid phases over an extended time. As result, •OH production capacity liquid reduced improved. The increased from 227-271 μmol kg-1 (within 1-11 cm depth) 500-577 499-902 after 50 day, 3 month, 1 year incubation, respectively. During drainage, dynamic triggered by consumption oxidation. ROS-trapping film situ capture revealed soil surface active zone for intense H2O2 production, limited observed deeper layers (>5 cm) due penetration. These findings provide more insights complex interplay between cycling redox transition zones fields.

Язык: Английский

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Electron transfer processes associated with structural Fe in clay minerals

Critical Reviews in Environmental Science and Technology, Год журнала: 2023, Номер 54(1), С. 13 - 38

Опубликована: Июнь 16, 2023

Fe-bearing clay minerals are widely distributed in soils, sediments, and rocks, representing a significant Fe pool the Earth's crust. The electron transfer (ET) from/to structural is crucial energy flux natural environment, which drives numerous biogeochemical processes contaminant transformation. Depending on types properties of both exogenous reactants as well aqueous chemistry, ET could involve interfacial through edge/basal planes interior inside minerals. This paper reviews important reactions between various reactants, including Fe-cycling microbes, redox-active organic compounds, heavy metals. Moreover, we discuss physical-chemical mechanisms develop models to illustrate thermodynamic kinetic constraints rate extent. On this basis, emphasize environmental implications associated with minerals, such their roles serving biogeobatteries for transformation, coevolution regulation greenhouse gas formation. Finally, research needs proposed advance our molecular-scale understanding utilize them mitigation human health.

Язык: Английский

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