Journal of Physical Chemistry C
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2021
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IF 4.126
Dai Sun,Yu-Le Wang,Peng-Yue Zhu,Hai-Tao Ren,Yong Liu,Song-Hai Wu,Shao-Yi Jia,Xu Han
Mechanisms involved in the photocatalytic oxidation of As(III) are complicated in that various oxidizing species (such as h+, •OH, and O2•–) have been suggested to play important roles in different photocatalytic systems. In this study, Bi2.15WO6 shows high reactivity in the photocatalytic oxidation of As(III) under visible light. Quenching experiments indicate that apart from h+, the surface superoxo (≡Bi–OO•) and peroxo species (≡Bi–OOH) formed on Bi2.15WO6 also contribute to As(III) oxidation. The increased production of H2O2 with increasingly consumed As(III) or with the addition of H-donors such as glucose and various phenolics further reveals that H-abstraction from As(III) or H-donors to ≡Bi–OO• and then to ≡Bi–OOH is an important pathway involved in H2O2 production and As(III) oxidation. In addition, various characterizations confirm that the As(III)–O–Bi(III) surface complexes formed on Bi2.15WO6 enhance the photocatalytic reactivity of Bi2.15WO6 via the ligand-to-metal charge transfer pathway. We therefore suggest that dissolved oxygen is sequentially reduced to ≡Bi–OO• and then to ≡Bi–OOH on Bi2.15WO6, accompanied by H-abstraction from adsorbed or aqueous As(III) to ≡Bi–OO• and ≡Bi–OOH with the formation of H2O2 and the oxidation of As(III). This work enriches our understanding of the mechanisms involved in the photocatalytic oxidation of As(III).
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2020
·Vol. 55
·期 25
·11310-11324
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IF 3.553
Ren Hai-Tao,Han Jing,Li Ting-Ting,Liang Yu,Jing Meng-Zhen,Jiang Si-Meng,Lin Jia-Horng,Lou Ching-Wen
Visible light response PAN@Ag–Ag 2 O/TiO 2 (PAN@AT) nanofibers with different mass ratios between Ag–Ag 2 O and TiO 2 were synthesized via a facile electrospinning technique and pH-induced precipitation reaction. X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscope analyses manifest the formation of Ag–Ag 2 O/TiO 2 heterojunctions, and Ag–Ag 2 O/TiO 2 nanoparticles are evenly distributed on PAN nanofibers. The fabricated nanofibers show a highly photocatalytic performance toward As(III) oxidation under visible light, and the conversion is 92.1% after 120-min reaction at pH 5.0 in the system of PAN@AT4. Furthermore, conversion of As(III) can retain 88.6% of the original activity after repeating four cycles, indicating the good recyclability of PAN@AT4 nanofibers. Quenching experiments and electron spin resonance spectra analysis further demonstrate that the predominate active species for As(III) oxidation by PAN@AT4 are h + and · OH. The enhanced catalytic activity of PAN@AT4 is therefore ascribed to the formation of Ag–Ag 2 O/TiO 2 heterojunctions on PAN surface and the efficient separation of photoinduced electron–hole pairs. This study provides a new material to oxidize reducing pollutants [such as As(III)] and also sheds light on the fabrication of recyclable photocatalysts.
研究领域:
材料科学
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环境工程
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纳米技术
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光化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Zhengliang Zhao,Jun Zhou,Zhu Shu
Piezo-catalysis is an emerging approach for green chemistry and water decontamination, which however is absent in aqueous arsenic remediation. Polymeric carbon nitride (PCN), a new piezoelectric material, was recently up-graded into crystalline carbon nitride, potassium poly(heptazine imide) (K-PHI). But the piezo-catalytic property of K-PHI is still blank in literature. This work first realized the oxidation of As(III) by piezo-catalysis and revealed the advanced piezo-catalytic property of K-PHI in comparison with PCN. A much superior (6.7 times faster) piezo-catalytic oxidation of As(III) was achieved on K-PHI, which benefits from its enhanced piezoelectric response deriving from the extended in-plane conjugation of heptazine units. Apart from the crystallinity of carbon nitride, the solution pH, sonication power and catalyst dosage were also found to be positively correlated with the piezo-catalytic As(III) oxidation. Additionally, h + and ·O 2 − rather than OH· were proved to be the active species. These findings not only supply a novel approach for As(III) pollution regulation in water bodies, but also point out the direction to improve the piezo-catalytic performance of carbon nitride.
研究领域:
环境科学
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材料科学
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水处理
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DOI
高影响因子
GREEN CHEMISTRY
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2019
·Vol. 21
·期 9
·2286-2294
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IF 9.405
Yuqing Qin,Fei Peng,Yonggang Hu
The oxidation of As(III) to As(V) is a critical process in the treatment of contaminated water. We found that 95% As(III) (10 mg L−1) could be rapidly oxidized to As(V) by a laccase–2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) system in 1 h. Based on this finding, we used Bacillus subtilis spores instead of laccase for As(III) oxidation with the same effect because the former had plenty of CotA–laccase on their surface. The catalytic ability of CotA protein and spores was confirmed by expressing the CotA protein and knocking out the cotA gene from wild-type spores. Both laccase– and spore–TEMPO systems displayed similar oxidation rate constants, Michaelis–Menten constants, and maximal velocities owing to the formation of the oxoammonium cation of TEMPO in the presence of dissolved oxygen. Several other laccase mediators such as 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic-acid) (ABTS), acetosyringone (AS), 1-hydroxybenzotriazole (HBT), 2-hydroxybutyl acrylate (HBA), violuric acid (VLA), 4-oxo-TEMPO, 4-amino-TEMPO, 4-methoxy-TEMPO, 4-hydroxy-TEMPO benzoate, and 4-hydroxy-TEMPO coupled with spores for As(III) oxidation were also investigated in detail. The spore–TEMPO system exhibited the highest oxidation efficiency and tolerated the addition of 10 mg L−1 Al3+, Ti4+, Cu2+, K+, Fe3+, Zn2+, Ni2+, Mg2+, Co2+, and Mn2+. Both laccase and spores recovered via ultrafiltration and centrifugation, respectively, could be reused for at least five cycles. The developed spore-based system has several advantages including eco-friendliness, ease of operation and storage, low cost, recyclability, sustainability, and without the need for enzyme purification. These findings may have promising implications for developing a new eco-friendly and cost-effective technology for the treatment of arsenic-containing water.
研究领域:
环境科学
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生物技术
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水处理
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微生物学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Yuxin Li,Zhimin Wang,Yuanfeng Wei,Ting Wang,Maosong Zhao,Jie Luo,Jun Zhou,Zhaoshuang Li,Kai Yin,Chengbin Liu
Water decontamination from arsenic-contaminated groundwater is critical to the health of millions of households worldwide. However, efficiently removing the low-adsorbing As(III) remains challenging. Herein, a multifunctional biocomposite bead UiO-66-NH 2 -Cl@PCB integrating defects, oxidation and adsorption properties was prepared to effectively remove As(III). The N -chlorosulfonamide bound within the embedded UiO-66-NH 2 -Cl oxidizes the lower-adsorbing As(III) to As(V), which could be effectively adsorbed by the defect-rich MOF, while the porous chitosan bead (PCB) host ensures the utilisation of the reactive sites of UiO-66-NH 2 -Cl. Using 1 g/L of UiO-66-NH 2 -Cl@PCB, 1 mg/L of As(III) can be reduced to under 10 μg/L in 300 min. Furthermore, similar As(III) removal efficiencies were achieved across a wide pH spectrum (3–9) or in the presence of interfering substances (anions, cations, organic matter). High concentrations of phosphate will inhibit its performance. As(III) removal followed the Freundlich isotherm modal, and its maximum removal capacity reached 58.09 mg/g at pH 7. Furthermore, at equilibrium concentrations of 10 μg/L, its As(III) removal capacity exceeded 10 mg/g. UiO-66-NH 2 -Cl@PCB can purify the As(III)-spiked groundwater to meet the drinking standard level. Using NaOH solution for regeneration, the removal efficiency maintained above 70 % in the fifth cycle. Additional chlorination treatment can significantly improve reusability. 2.4 g of UiO-66-NH 2 -Cl@PCB packed fixed-bed column was capable of purifying 3820 BV of groundwater containing 100 μg/L of As(III). The proposed UiO-66-NH 2 -Cl@PCB has the potential to be an easy-to-use and reliable material for efficient As(III) removal.
研究领域:
环境科学
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材料科学
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水处理技术
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化学工程
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吸附与催化
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）