Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Yanli Zhang,Jian Li,Jianyu Cai,Shuangye Li,Xing Fan,Liyun Song,Ruixue Guo,Jiasheng Liu
In this study, a series of γ-Fe 2 O 3 -modified V 2 O 5 -MoO 3 /TiO 2 (VMT) catalysts was prepared by wet impregnation method. The γ-Fe 2 O 3 -modified catalysts exhibited excellent catalytic performance, and 1.25 wt% γ-Fe 2 O 3 content improved the deNO x efficiency at 150 °C from 54% (unmodified VMT catalyst) to 84% (modified catalyst). BET, XRD, XPS, NH 3 -TPD, H 2 -TPR, and in situ DRIFTs were employed to characterize the physicochemical properties and reaction mechanisms of the catalysts. The introduction of γ-Fe 2 O 3 increased the V 5+ /V 4+ ratio, surface chemisorbed oxygen content, redox ability, and a number of acid sites in the prepared catalysts. XPS confirmed the addition of γ-Fe 2 O 3 introduced new charge transfer pathways (Fe 3+ /Fe 2+ ↔ V 5+ /V 4+ ). In situ DRIFTs suggested that the addition of γ-Fe 2 O 3 to the catalyst significantly increased the adsorption capacity of catalyst for NH 3 and NO x , while also exerting a strong activating effect on the adsorbed NH 3 . Furthermore, selective catalytic reduction over the VMT and 5PEG@1.25Fe-VMT catalysts followed the Eley-Rideal (E-R) mechanism. At temperatures above 200 °C, the 5PEG@1.25Fe-VMT catalyst also followed the Langmuir-Hinshelwood (L-H) mechanism.
研究领域:
环境科学
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催化化学
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产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Jianhui Zhao,Yuanzhou Wang,Ning Li,Shaopo Wang,Junli Yu,Xinxin Li
In this work, the magnetic γ-Fe 2 O 3 –MnO 2 bifunctional catalyst with oxygen vacancy was synthesized for peroxymonosulfate (PMS) activation under visible light. The activity of γ-Fe 2 O 3 –MnO 2 was investigated by ciprofloxacin (cipro) degradation. Results showed that 98.3% of cipro (50 μM) was removed within 30 min in visible-light/PMS system mediated by γ-Fe 2 O 3 –MnO 2 (2:1) with fine-tuned oxygen vacancy. The cipro degradation data fitted well with pseudo-first-order kinetic model with the highest kinetic constant of 0.114 min −1 . Besides, the γ-Fe 2 O 3 –MnO 2 exhibited stability, recyclability and practicability. High selectivity for cipro degradation was observed with coexisting anions in visible-light/γ-Fe 2 O 3 –MnO 2 /PMS system. Furthermore, the enhanced mechanism of PMS activation under visible light with γ-Fe 2 O 3 –MnO 2 was proposed. The appropriate oxygen vacancy enhanced the separation of photo-induced carriers and Z scheme heterostructure maintained the highest redox potential . Accordingly, the synergistic effect of photocatalysis and PMS activation enhanced cipro degradation. Free radical and non-radical species including , h + , 1 O 2 , • OH and co-existed in the coupled system. Impressively, this study provides a handy approach for oxygen vacancy regulation in metallic oxides composite and an easily recycled catalyst with high-activity in coupled oxidation system towards antibiotic degradation.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2023
·
IF 2.2
Nana Sun,Jianbo Hu,Lisha Shen,Huina Sun,Ding Wang
The effects of modified γ-Fe2O3 magnetic nanoparticles having various sizes at different mass fractions on the stability of heavy oil-in-water emulsions were compared. The zeta potential, wettability, oil-water interfacial tension, apparent viscosity, and oil droplet distribution of the emulsions were measured. The optimal size of the γ-Fe2O3(-COOH) magnetic nanoparticles was 2–3 μm, and this resulted in the lowest water-separation rate (23.72% at 4 hours), greatest electrostatic repulsion, weakest hydrophilic effect, lowest interfacial tension, greatest migration resistance, and smallest and most uniform oil droplet distribution. In addition, the stability of the emulsions increased and then decreased as the mass fraction of γ-Fe2O3 (-COOH) magnetic nanoparticles increased because of the increased electrostatic repulsion and decreased migration resistance. This in-depth analysis of the effect of modified magnetic nanoparticle size on the stability of oil-in-water emulsions provides comprehensive theoretical support for achieving viscosity and resistance reduction in an environmentally friendly manner.
研究领域:
材料科学
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石油工程
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 5
·057511
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IF 4.316
Xin-Qin Cai,Kai Zhu,Bo-Tao Liu,Qing-Yu Zhang,Yu-Hui Luo,Dong-En Zhang
In this work, γ-Fe2O3/CNTs composite was facile synthesized by simple hydrothermal method and hydrazine hydrate treatment at low temperature (CNTs = carbon nanotubes). The result of VSM shows that the saturation magnetization of Fe2O3/CNTs composites increase from 0 to 1.29 emu g−1 after hydrazine hydrate treatment, indicating that the Fe2O3 in the composite transforms from α phase to γ phase. Moreover, the electrochemical properties of both α-Fe2O3/CNTs and γ-Fe2O3/CNTs was studied. Compared with α-Fe2O3/CNTs, γ-Fe2O3/CNTs shows enhanced electrochemical performance toward paracetamol determination. Under optimum condition, the γ-Fe2O3/CNTs modified electrode exhibits two linear ranges of 2.5 μM−385 μM and 593 μM−1550 μM and a low detection limit of 0.046 μM. In addition, the constructed sensor can be successfully utilized for detecting paracetamol in different water bodies. This work provides a new clue for the design and construction of excellent electrochemical sensor for paracetamol determination.
研究领域:
材料科学
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分析化学
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DOI
高影响因子
Materials Today Chemistry
·
2022
·
IF 7.613
Yuan Wang,Xuemei Liu,Quyun Chen,Tian C. Zhang,Like Ouyang,Shaojun Yuan
Addressing arsenite pollution in groundwater has drawn great attention. It is attractive to pre-oxidize highly mobile As(III) to relatively low-toxic As(V) with a subsequent adsorption separation process. Herein, BiOI anchoring on γ-Fe 2 O 3 is performed to synthesize BiOI/γ-Fe 2 O 3 core–shell nanoparticles for efficient removal of As(III) via a simultaneous photocatalytic oxidization–adsorption process. The physical and chemical structures of BiOI/γ-Fe 2 O 3 are investigated by transmission electron microscopy , Fourier transform infrared spectroscopy , and X-ray diffraction measurements. The photoluminescence and electron spin resonance (ESR) characterization were employed to ascertain the possible reaction mechanism of visible-light-driven photocatalytic oxidation of As(III). Such BiOI/γ-Fe 2 O 3 delivers a superior As(III) removal capability under visible light irradiation with an arsenic removal efficiency of 99.8% within 180 min, higher than those of BiOCl/γ-Fe 2 O 3 (81.7%) and BiOBr/γ-Fe 2 O 3 (98.9%). The optimal BiOI/γ-Fe 2 O 3 (molar ratio of 2:1) is obtained by rationally adjusting the molar ratio of BiOI to γ-Fe 2 O 3 . The as-synthesized BiOI/γ-Fe 2 O 3 performs well in a wide pH range of 2–8. Only coexisting PO 4 3− anions have a significant effect on the As(III) removal. The free radical trapping experiment and ESR results demonstrate that the ⋅O 2 − and h + are the main active substances for the photocatalytic oxidation of As(III) on BiOI/γ-Fe 2 O 3 . This work not only gives a novel magnetic core–shell nanoparticle photocatalyst for efficient photocatalytic oxidation and adsorption of As(III) but also offers a new strategy to rationally design BiOX for its related practical applications.
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
RSC Advances
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2014
·Vol. 4
·期 23
·11788-11793
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IF 3.708
Yanyan Fang,Hailian Xiao,Ning Sui,Manhong Liu,William W. Yu
Supported Pt nanocatalysts with controlled particle size and size distribution were prepared by immobilizing Pt colloids on different iron oxide supports (γ-Fe2O3, Fe3O4, Fe2O3) via physical adsorption. These catalysts were used to catalyze the liquid phase hydrogenation of o-chloronitrobenzene (o-CNB) to o-chloroaniline (o-CAN) under mild reaction conditions (298 K, 0.1 MPa). The Pt/γ-Fe2O3 exhibited higher catalytic selectivity and activity than other similar works (selectivity = 99.9%, activity = 0.20 molo-CNB/(molPt s)). The stability of the Pt/γ-Fe2O3 was investigated, and the result showed that higher drying temperature could increase the stability of the catalyst.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 20
·12358-12369
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IF 2.599
Ji Shengning,Zhang Zhiming,Jiang Xiaohui,Yu Liangmin
The three-layer core–shell–shell γ-Fe 2 O 3 –SiO 2 –poly (3,4-ethylenedioxythiophene) (PEDOT) nanocomposite has been successfully synthesized by a facile chemical process followed by a detailed investigation of morphology, composition, electromagnetic, and microwave absorption properties. The electrical conductivity of γ-Fe 2 O 3 –SiO 2 –PEDOT nanocomposites was as high as 3.34 S cm −1 , and the saturation magnetization was in the range of 1–7 emu g −1 . The minimum reflection loss reached −27.5 dB at 13.8 GHz with a matching layer thickness of 2.0 mm and an effective absorption bandwidth (< −10 dB) of about 4.1 GHz (12.0–16.1 GHz). The excellent microwave absorbing performance of this nanocomposite is due to proper impedance matching and the synergistic interaction of dielectric loss, the magnetic loss, and core–shell microstructure. Moreover, the electromagnetic and microwave absorbing properties of γ-Fe 2 O 3 –SiO 2 –PEDOT nanocomposites can be regulated by changing the dosage of functionalized γ-Fe 2 O 3 –SiO 2 .
研究领域:
材料科学
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电磁学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Jiankang Wang,Taiping Xie,Guokang Han,Quanxi Zhu,Yajing Wang,Yuan Peng,Songli Liu,Zhongping Yao
Cost-effective and low-toxicity of MnO 2 is regarded as a promising alternative to Co-based catalyst for peroxymonosulfate (PMS) activation to degrade recalcitrant organic pollutants. However, the sluggish Mn(IV)/Mn(III) redox cycling and limited specific surface area greatly hampered its wide application. To solve this challenge, a mesoporous γ-Fe 2 O 3 @MnO 2 magnetic catalyst with SiO 2 assistance (s-γ-Fe 2 O 3 @MnO 2 ) was synthesized. Physicochemical characterization confirmed part MnO 2 was coated on γ-Fe 2 O 3 surface while the other existed independently. Furthermore, BET surface area of s-γ-Fe 2 O 3 @MnO 2 was more than two times that of the counterpart without SiO 2 assistance (ws-γ-Fe 2 O 3 @MnO 2 ). s-γ-Fe 2 O 3 @MnO 2 exhibited enhanced PMS activation capacity with 97.6% phenol removal efficiency within 80 min, superior to other samples. Various influencing parameters on phenol oxidation were optimized. Reactive oxygen species (ROS) scavenging experiment and electron paramagnetic resonance (EPR) validated co-existence of hydroxyl radicals (·OH) and sulfate radicals (SO 4 · − ) as well as singlet oxygen ( 1 O 2 ) during PMS activation. However, phenol degradation was a non-radical oxidation process dominated by 1 O 2 . A rational reaction mechanism was proposed. Fe(II) promoted Mn(IV)/Mn(III) redox cycling and the enlarged surface area derived from SiO 2 mediated templating synthesis were responsible for the enhanced phenol degradation. This strategy can give a guidance for synthesis of highly efficient catalyst for sewage remediation.
研究领域:
环境科学
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催化化学
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产品关联
DOI
高影响因子
Russian Journal of Physical Chemistry A
·
2019
·Vol. 93
·期 7
·1343-1348
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IF 0.581
Liang An,Zhao Xiaolian,Xu Chengkang,Yan Zhaoxiong,Yang Zhihua,Xu Zhihua
Abstract In this work, magnetically separable and recyclable γ-Fe 2 O 3 /HAp/Ag 3 PO 4 composite microsheets were prepared by hydrothermal and in-situ ion-exchange methods, in which photoactive Ag 3 PO 4 nanoparticles and magnetic γ-Fe 2 O 3 nanoparticles are distributed on the hydroxyapatite (HAp) microsheets. Characterization of the samples was performed by XRD, FE-SEM, EDS, FT-IR, and VSM. The photocatalytic performance of the samples was checked by investigating the degradation process of four different organic dyes under visible-light irradiation. Photocatalytic experiments reveal that all γ-Fe 2 O 3 /HAp/Ag 3 PO 4 samples show certain photocatalytic activities for the degradation of OII, and the degradation rate is different when diverse γ-Fe 2 O 3 /HAp/Ag 3 PO 4 samples are added into the OII solution. FHA-4 exhibits the highest degradation rate, and it could degrade different organic dyes, which means it has the potential to be applied into the treatment of complex wastewater containing different organic dyes. In addition, FHA-4 exhibits ferromagnetic feature, and can be easily separated from water by an external magnetic field.
研究领域:
材料科学
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环境科学
·
纳米技术
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DOI
高影响因子
Journal of Materials Chemistry B
·
2013
·Vol. 1
·期 10
·1491-1500
·
IF 0
Zhi-Gang Wang,Gong Cheng,Yan-Lin Liu,Ji-Lin Zhang,De-Hui Sun,Jia-Zuan Ni
The multifunctional microspheres consisting of the magnetic γ-Fe2O3 core and the affinity REVO4 (RE = Sm, Dy, Ho) shell have been synthesized via the homogenous precipitation–calcination–ion exchange three-step synthetic route. Their morphologies, structures, surface properties, and magnetisms were characterized, respectively. SEM and TEM images indicate that they all have an average size of about 400 nm and very rough surfaces. The TEM images further reveal that the γ-Fe2O3@REVO4 microspheres are all core–shell structures and the REVO4 shells are about 55–60 nm in thickness. The XRD pattern analyses show that the magnetic γ-Fe2O3 cores belong to cubic structure and the REVO4 (RE = Sm, Dy, Ho) shells are composed of their corresponding tetragonal major phases. HRTEM images, FTIR spectra and EDS further demonstrate the formations of tetragonal REVO4 shells based on checkup of the corresponding lattice fringes, characteristic IR absorption peaks and element signals. Their potentials for selective capture, rapid separation, and convenient mass spectra (MS) labeling of the phosphopeptides from complex proteolytic digests are explored and evaluated for the first time. The experimental results show that the magnetic γ-Fe2O3@REVO4 core–shell structured microspheres have high selective affinity for the phosphopeptides. The trapped phosphopeptides can be rapidly isolated by an external magnetic field, and can be easily identified by characteristic MS signals from 80 Da mass losses in the mass spectra (MS). Additionally, the γ-Fe2O3@REVO4 affinity materials can be reused after recovery.
研究领域:
材料科学
·
分析化学
·
生物化学
✓ 已验证
DOI
PubMed
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Jinghang Sun,Zhongmin Fang,Xianfa Zhang,Linjie Li,Xiaodan Zhao
Advanced oxidation processes (AOPs) based on sulfite activation have been demonstrated to achieve cost-effective and highly efficient abatement of organic pollutants. In this work, the manganese-doped γ-Fe 2 O 3 catalyst (Mn-γ-Fe 2 O 3 ) is constructed based on the properties of Mn(II) with surface oxygen vacancy regulation and as an active site for sulfite activation. The increase of the Mn(II) doping ratio is favorable for the generation of surface oxygen vacancy with the content being enhanced more than two times when the Mn(II) doping ratio is 0.09 compared with that of γ-Fe 2 O 3 . The iohexol (IOX) abatement efficacy by sulfite activation with Mn-γ-Fe 2 O 3 is positively correlated with the oxygen vacancy content, in which SO 4 •− is the major free radical responsible for IOX degradation and HO • plays a secondary role. The presence of surface oxygen vacancy on the Mn-γ-Fe 2 O 3 exhibits low electrochemical resistance. The theoretical calculations support the enhancement of the electron transfer between Mn-γ-Fe 2 O 3 and sulfite with more negative adsorption energy and strong interaction of iron and manganese atoms. By analyzing the valence variation before and after the reaction, both > Mn(II) and > Fe(III) can participate in the acceleration of sulfite autoxidation process to generate radicals. Application of surface oxygen vacancy enriched Mn-γ-Fe 2 O 3 for sulfite activation exhibits good adaptability to different real water matrices and thus have some potential for practical applications.
研究领域:
环境科学
·
催化化学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Zhuan Wang,Bo Yang,Xueying Zhao,Yushuai Chen,Dandi Wei,Lijuan Zhang,Xintai Su
Oxygen evolution reaction (OER) is the bottleneck of photocatalytic water splitting due to the slow four-electron transfer kinetics, and the construction of ultrathin materials is considered to be an effective means to solve the above problem. Herein, ultrathin γ-Fe 2 O 3 nanosheets (Fe 2 O 3 -NS) were prepared by a facile solution reduction-low temperature calcination method. The prepared photocatalyst has a leaf-like morphology with an average thickness of 2.0 nm and a large number of slit-like pores. Compared with γ-Fe 2 O 3 bulk, Fe 2 O 3 -NS exhibits excellent photocatalytic OER activity. The apparent quantum yield (AQE) and oxygen yield (measured at 420 nm) are 12.95% and 57.04%, respectively. The OER efficiency is superior to those reported iron oxide photocatalysts. This excellent performance may benefit from the ultrathin porous structure, appropriately narrow bandgap, and abundant oxygen vacancies . In addition, the photocatalyst shows good cycling stability, retaining 91.5% of the initial capacity in the fifth cycle test, which may be attributed to the magnetic cycling capability and good structural stability. This study confirms that Fe 2 O 3 -NS is a competitive candidate material for photocatalytic oxygen evolution and provides ideas for the design and construction of other defect-rich metal oxide nanosheets.
研究领域:
材料科学
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环境科学
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能源科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）