APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Yaru Wang,Jianjun Zhao,Xianqiang Xiong,Shengwei Liu,Yiming Xu
Anatase TiO 2 is the most studied environmental photocatalyst, but its efficiency is still not high enough to enable application. Herein we report a positive effect of Ni 2+ ions on the photocatalytic reaction in neutral aqueous solution. On addition of 1 mM Ni(ClO 4 ) 2 , the rates of phenol oxidation on TiO 2 and 0.5 wt.% Pt/TiO 2 increased by factors of 2.1 and 8.0, respectively. Meanwhile, the formation of organic intermediate was reduced, and the removal of total organic content was enhanced. Interestingly, Ni 2+ concentration did not change with irradiation time. Moreover, a maximum rate of phenol degradation was observed with Ni 2+ ions, occupying half the surface of TiO 2 or Pt/TiO 2 , where Ni(OH) + was more active than Ni(OH) 2 . X-ray photoelectron spectroscopy identified a Ni 3+ species produced in absence of phenol. A (photo)electrochemical study revealed that Ni 2+ oxidation was favored over H 2 O oxidation, whereas Ni 2+ and Pt inhibited and facilitated O 2 reduction, respectively. It is proposed that the adsorbed Ni(OH) + on TiO 2 is oxidized to Ni 3+ by the photogenerated holes of TiO 2 , followed by regeneration through phenol oxidation. The Ni 2+ -catalyzed organic oxidation then promotes the Pt-catalyzed O 2 reduction, and vice visa, resulting into the greatly improved efficiency of charge separation. This work highlights the possibility of Ni 2+ ions as the hole mediator of organic oxidation over a semiconductor.
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
Nanomaterials
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2022
·Vol. 12
·期 18
·3089
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IF 5.719
Li Tan,Yiming Chen,Didi Li,Shaobin Wang,Zhimin Ao
An in situ photo-Fenton system can continuously generate H2O2by photocatalysis, activating H2O2in situ to form strong oxidizing ·OH radicals and degrading organic pollutants. A WSe2/g-C3N4composite catalyst with WSe2as a co-catalyst was successfully synthesized in this work and used for in situ photo-Fenton oxidation. The WSe2/g-C3N4composite with 7% loading of WSe2(CNW2) has H2O2production of 35.04 μmol/L, which is fourteen times higher than pure g-C3N4. The degradation efficiency of CNW2 for phenol reached 67%. By constructing an in situ Fenton-system, the phenol degradation rate could be further enhanced to 90%. WSe2can enhance the catalytic activity of CNW2 by increasing electron mobility and inhibiting the recombination of photogenerated electron–hole pairs. Moreover, the addition of Fe2+activates the generated H2O2, thus increasing the amount of strong oxidative ·OH radicals for the degradation of phenol. Overall, CNW2 is a promising novel material with a high H2O2yield and can directly degrade organic pollutants using an in situ photo-Fenton reaction.Keywords:WSe2/g-C3N4;visible light;in situ photo-Fenton;phenol degradation
研究领域:
环境科学
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材料科学
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催化
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DOI
PubMed
高影响因子
BIOCHEMICAL JOURNAL
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2023
·Vol. 480
·期 21
·1753-1766
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IF 4.1
Cui Mengyu,Wei Yifeng,Tan Jason,Li Tong,Jiao Xinan,Zhou Yan
Phloroglucinol (1,3,5-trihydroxybenzene) is an important intermediate in the degradation of flavonoids and tannins by anaerobic bacteria. Recent studies have shed light on the enzymatic mechanism of phloroglucinol degradation in butyrate-forming anaerobic bacteria, including environmental and intestinal bacteria such as Clostridium and Flavonifractor sp. Phloroglucinol degradation gene clusters have also been identified in other metabolically diverse bacteria, although the polyphenol metabolism of these microorganisms remain largely unexplored. Here, we describe biochemical studies of polyphenol degradation enzymes found in the purple non-sulfur bacterium Rubrivivax gelatinosus IL144, an anaerobic photoheterotroph reported to utilize diverse organic compounds as carbon sources for growth. In addition to the phloroglucinol reductase and dihydrophloroglucinol cyclohydrolase that catalyze phloroglucinol degradation, we characterize a Mn2+-dependent phloretin hydrolase that catalyzes the cleavage of phloretin into phloroglucinol and phloretic acid. We also report a Mn2+-dependent decarboxylase (DeC) that catalyzes the reversible decarboxylation of 2,4,6-trihydroxybenzoate to form phloroglucinol. A bioinformatics search led to the identification of DeC homologs in diverse soil and gut bacteria, and biochemical studies of a DeC homolog from the human gut bacterium Flavonifractor plautii demonstrated that it is also a 2,4,6-trihydroxybenzoate decarboxylase. Our study expands the range of enzymatic mechanisms for phloroglucinol formation, and provides further biochemical insight into polyphenol metabolism in the anaerobic biosphere.
研究领域:
微生物学
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生物化学
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环境科学
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DOI
PubMed
高影响因子
Journal of Physical Chemistry C
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2015
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IF 4.772
Xianqiang Xiong,Haihang Chen,Yiming Xu
Various methods that aim to improve the photocatalytic activity of TiO2 have been reported in the literature. Herein, we report that addition of CuWO4 into the aqueous suspension of TiO2 can result in significant enhancement in the rate of phenol degradation. As the amount of CuWO4 increased, the rate of phenol degradation increased and then decreased. A maximum rate of phenol degradation observed with 2 wt % CuWO4 was about 2.83 times that in the absence of CuWO4. A similar result was also observed with CuO. However, six consecutive tests showed that CuWO4/TiO2 was much more stable than CuO/TiO2, due to the very high stability of CuWO4 against photocorrosion. The improved activity of TiO2 is not due to CuWO4 and CuO themselves and also does not match their solubility in aqueous solution. Moreover, for the generation of OH radicals, and for the decomposition of H2O2 in aqueous solution, CuWO4/TiO2 was also more active than TiO2. Through a (photo) electrochemical measurement, a possible mechanism is proposed, involving electron transfer from the irradiated TiO2 to CuWO4 that facilitates the charge separation of TiO2 and consequently accelerates reactions at interfaces.
研究领域:
环境科学
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材料科学
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化学
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产品关联
DOI
高影响因子
CATALYSIS TODAY
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2015
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IF 3.893
Minli Niu,Rongshu Zhu,Fei Tian,Kelin Song,Gang Cao,Feng Ouyang
A series of carbon modified BiVO 4 (C–BiVO 4 ) photocatalysts were synthesized by impregnation calcination method of BiVO 4 with glucose, sucrose and cellulose as precursors, respectively. The prepared photocatalysts were characterized by XRD, HR-TEM, SEM, Raman, BET, UV–vis DRS and PL. Their photocatalytic activities were investigated by degradation of phenol under the visible light. The precursor and loading of carbon had remarkable effects on physical–chemical properties of samples and degradation activities of phenol. The increase of the number of carbon ring in precursors led to a better crystallinity, smaller grain size, larger surface area and higher separation efficiency of electron–hole pairs. The increase of loading led to a smaller catalyst grain size, larger surface area, higher visible light absorption and higher separation efficiency of electron–hole pairs. The results showed that the 0.5 wt.% of C–BiVO 4 –cellulose has the best photocatalytic activity and degraded 88.7% of 5 mg/L phenol. Besides, addition of 25 mmol KBrO 3 as an electron capture agent can degrade 27.4% of 1000 mg/L phenol. The degradation efficiency of the same system above mentioned under sunlight irradiation was 22.6%. In addition, the relationship between the photocatalytic activity of C–BiVO 4 and its physical–chemical properties was also discussed.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
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2023
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IF 2.8
Ruizhi Feng,Ying Zhang,Caigan Yan,Haihe Xiao,Xiaobiao Zhu,Xiaohui Wang
Electrochemical advanced oxidation processes (EAOPs) has attracted wide attention to researchers on all walks of life for the treatment of stubborn pollutants because of the strong oxidizing properties. However, the electrode materials currently developed have problems such as short life and low catalytic activity. In this work, the modification of PbO 2 electrode was started by introducing into blue nanotubes (Blue-TiO 2 -NTs) based on the titanium plate to enhance the conductivity of the electrode. Then the β-PbO 2 active layer was optimized by using cerium (Ce) and dodecyl trimethyl ammonium bromide (CTAB) through the method of electrodeposition to improve the electrocatalytic oxidation and stability. In the experiment of electrochemical oxidation, the degradation efficiency of phenol (100 mg/L) reached more than 96% after 120 min on the Blue-TiO 2 /PbO 2 -Ce-CTAB electrode. To further investigate the optimization mechanism of the Blue-TiO 2 /PbO 2 -Ce-CTAB anode in the electrocatalytic oxidation process, the surface structure, morphology, volt-ampere charge, oxygen evolution potential, and charge transfer resistance were evaluated. The result showed that the addition of CTAB reduced the crystal particles of PbO 2 , higher specific surface area of the electrode longitudinally by the Ce element, lower oxygen evolution potential, and smaller the resistance of charge transfer. Finally, the service life of the electrode was 6792 h by the accelerated life test on the current density of 25 mA cm −2 . The energy consumption after 240 min of degradation was 0.079 kWh gCOD −1 .This research proves that the Blue-TiO 2 /PbO 2 -Ce-CTAB electrode has potential application value in the degradation of phenol wastewater.
研究领域:
环境科学
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING
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2011
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IF 1.107
Zhiqiao He,Angliang Zhang,Yu Li,Shuang Song,Zhiwu Liu,Jianmeng Chen,Xinhua Xu
Ozonation combined with UV irradiation (UV/O3) is an advanced oxidation technique that is very promising for the destruction of organic compounds in aqueous solution. In this study, chlorophene was chosen as a model substrate to investigate the effects of pH, initial substrate concentration, ozone dose, and UV light intensity in degradation experiments. The pseudo–first-order rate constant for total organic carbon (TOC) removal was 2.4 × 10−2, 9.8 × 10−4, and 6.4 × 10−2 min−1 for O3, UV, and UV/O3 treatment, respectively. Clearly, UV-enhanced ozonation leads to a synergetic increase in the overall degradation efficiency. Comparative experiments were performed to investigate the effect of the matrix (distilled water or sewage) on chlorophene removal. The organic compounds in sewage retarded the rate of chlorophene removal by 38%, probably by competitively reacting with the oxidizing agent and screening light. The compound 2-benzoylbenzo-1,4-quinone, benzo-1,4-quinone, hydroquinone and maleic acid were identified as primary intermediates by gas chromatography-mass spectrometry. The concentrations of acetic, formic and oxalic anions were detected by ion chromatography. A possible degradation pathway is proposed on the basis of the reaction products identified.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Chun Pei,Ji-Hua Zhu,Leyang Lv
Semiconductor photocatalysts suffer from low photocatalytic quantum efficiency , diminished solar energy utilization, and inadequate photostability, thereby impeding their widespread adoption. Meanwhile, graphene emerges as an ideal substrate material for fabricating high-performance composite photocatalysts owing to its distinctive single-layer sp 2 -hybridized carbon atom arrangement, substantial specific surface area, exceptional electron conductivity, and pronounced transparency. In this study, a graphene-anatase-rutile core-shell structured nanofiber mat architecture is successfully synthesized by sol-gel-assisted coaxial electrospinning with high-temperature thermal treatment. This innovative architecture effectively narrows the bandgap of TiO 2 and synergizes adsorption and catalysis processes to achieve heightened catalytic efficiency and prolonged stability. Photocatalytic assays conducted under visible light irradiation demonstrate the excellent photocatalytic activity and stability of the graphene-titanium dioxide hybrid material during the degradation of phenol . The kinetics and mechanism of the phenol degradation of the nanofiber mat have been explored. Furthermore, the unique mesh-like configuration intrinsic to the nanofiber assembly confers sedimentation and recyclability upon the composite material.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2020
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IF 4.3
Tao Huang,Jundong Zhu,Shengzhuo Ge,Tianyu Guo,Chongwen Jiang,Le Xie
Heterogeneous photo-Fenton reaction using BiFeO 3 as catalyst was considered as an efficient environmental remediation technique. However, its low catalytic performance limited its application. In this work, CdSe QDs with high electron mobility, small size effect and rich surface properties were loaded on BFO surface by stirring impregnation method. The photo-Fenton catalytic performance of catalysts under visible light irradiation was evaluated by the degradation of phenol. The results showed that the BFO with CdSe QDs uniformly distributed on the surface shows much better photo-Fenton degradation of phenol performance than that of pure BFO. Moreover, when the load content of CdSe QDs comes to 0.5 wt%, the degradation efficiency of phenol increased from 41.5% to 98.5% within 60 min. The results of photochemical experiments confirmed that composite catalyst had a good ability to separate photo-induced carriers and the experiments of free radicals trapping showed that the holes and OH radicals were important active substances. Based on the above research, the possible mechanism of photo-Fenton reaction of catalyst was expounded. Excellent photo-Fenton catalytic performance and superior stability make this material showing a good application prospect for the degradation of organic pollutants in wastewater.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
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IF 6.361
Qi Wang,Hong Wu,Qiaoyuan Gao,Dagang Lin,Yongjie Fan,Ran Duan,Yanqing Cong,Yi Zhang
Plasmonic Bi 0 modified BiOI-Bi 2 O 3 composite (Bi/BiOI-Bi 2 O 3 ) was prepared via in situ UV reduction method. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) techniques were carried out to identify the formation of semimetal Bi 0 . The results indicated that the dot-like bismuth particles were originated from the partial reduction of lattice Bi 3+ to Bi 0 by accumulated conduction band electrons in BiOI-Bi 2 O 3 . The as-prepared ternary composite exhibited enhanced visible-light-response, decreased charge transfer impedance and higher charge carrier density relative to unmodified BiOI-Bi 2 O 3 . Due to synergistic effect between plasmonic Bi 0 and BiOI-Bi 2 O 3 heterojunction , dramatically enhanced photocatalytic activity for phenol degradation can be achieved. After 3.5 h visible light irradiation, the value for phenol removal efficiency was ca. 60% and 100% on BiOI-Bi 2 O 3 and Bi/BiOI-Bi 2 O 3 , respectively. The calculated zero-order rate constant on Bi/BiOI-Bi 2 O 3 was 1.7 and 3.9 times that on BiOI-Bi 2 O 3 and Bi 2 O 3 , respectively. In addition to phenol, organic dyes (zwitterionic RhB , cationic MB and anionic Org II) were also used as model pollutants. Pronounced photocatalytic degradation by Bi/BiOI-Bi 2 O 3 can be observed, further confirming the importance of Bi 0 . Trapping experiments using different scavengers indicated that photogenerated holes were major active species during the degradation of phenol. Furthermore, good stability was also observed in 5 successive cyclic runs. This study opens a new strategy for in situ preparation of plasmonic Bi 0 modified composite.
研究领域:
材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
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2022
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IF 8.943
Qiang Wang,Haibo Liu,Peixun Zhai,Fuwei Sun,Tianhu Chen,Ziyang Chu,Dong Chen,Xuehua Zou
In this study, a new low-cost carbon-based material was prepared via the carbonization of methylene blue adsorbed halloysite (CMH) at different temperatures in a nitrogen atmosphere, which was named CMH-T (T-Temperature). The performance of CMH-T was explored and the effects of initial pH values, catalyst dosage, phenol (PE) concentrations, peroxymonosulfate (PMS) concentrations, and water background compounds on PE degradation were investigated systematically. The results indicated that CMH800 exhibited the best performance to activate PMS for degrading PE. Specifically, 92% PE was degraded within 30 min with a constant rate ( k obs ) of 0.1186 min −1 in the CMH800/PMS system. Furthermore, CMH800 was efficient over a wide pH range (pH 3–9) and showed a slight inhibition to inorganic anions. Quenching experiments, electron spin resonance (ESR) analysis, and electrochemical analysis confirmed that PE was degraded through non-radical pathways dominated by single oxygen ( 1 O 2 ) and mediated electron transfer processes in the CMH800/PMS system. In addition, the predicted toxicity of intermediates through ECOSAR software based on QSAR (Quantitative Structure - Activity Relationship) model indicated that most of the intermediates had a low risk to water environment. Therefore, the CMH800 has a good potential for wastewater treatment applications.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2021
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IF 5.455
Mengyue Li,Yi Zhai,Xubin Zhang,Fumin Wang,Guojun Lv,Mengyao Li,Qing Zhang,Yongkui Liu
It is of great significance to develop a novel strategy to synthesize hollow zeolite without using mesoporogens due to its extremely short diffusion length. Ferric nitrate as a common iron source and structure direction agent has been used for synthesizing Fe-doped zeolite. However, the effect of ferric nitrate on the morphology of zeolite has not yet been elaborated. Here, we successfully synthesized hollow MFI zeolite with a framework iron-rich surface by using ferric nitrate as an iron source and seed-assistant strategy. It is the first time to propose that inorganic iron has the hollow structure-directing effect. Herein, by comparatively investigated the effect of iron content on the structure and evolution process of hollow zeolite, a novel crystallization mechanism has been proposed based on the competitive relationship between crystallization and dissolution rates. When the Si/Fe ratio reaches 25, the internal dissolution rate of seeds is faster than the surface crystallization rate of zeolite, the hollow structures are acquired. The obtained Fe-doped hollow zeolite exhibits superior catalytic performance for the reaction of phenol degradation. In this reaction, the higher effectiveness factor (η) close to 1 of Fe-doped hollow zeolite confirmed by calculations indicates its superior mass transferability.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）