Catalysts
·
2023
·Vol. 13
·期 7
·1057
·
IF 3.9
Rongwei Zheng,Ruifan Tan,Yali Lv,Xiaoling Mou,Junqiao Qian,Ronghe Lin,Ping Fang,Weidong Kan
Iron-based materials are widely applied in Fenton chemistry, and they have promising prospects in the processing of wastewater. The composition complexity and rich chemistry of iron and/or oxides, however, hamper the precise understanding of the active sites and the working mechanism, which still remain highly controversial. Herein, iron oxides of four different model systems are designed through a conventional precipitation method plus H2reduction treatment. These systems feature Fe@Fe3O4with abundant oxygen vacancy, Fe0and Fe3O4particles with interface structures, and Fe3O4-dominated nanoparticles of different sizes. These materials are applied in the decomposition of methyl orange as a model reaction to assess the Fenton chemistry. The Fe@Fe3O4with core–shell structures exhibits significantly higher decomposition activity than the other Fe3O4-rich nanoparticles. A thin Fe3O4layer formed by auto-oxidation of iron particles when exposed to air can boost the activity as compared with the Fe0and Fe3O4particles with interface structures but poor oxygen vacancy. The unique hetero-structure with the co-existence of both metallic iron and oxygen vacancy displays excellent redox propensity, which might account for the superior Fenton activity. This finding provides a new perspective to understand and design highly efficient iron-based Fenton catalysts.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2016
·
IF 2.208
Cancan Xu,Rui Liu,Lvjun Chen,Jialu Tang
Ni/Fe-Fe 3 O 4 nanocomposites were synthesized for dechlorination of 2,4-dichlorophenol (2,4-DCP). The effects of the Ni content in Ni/Fe-Fe 3 O 4 nanocomposites, solution pH, and common dissolved ions on the dechlorination efficiency were investigated, in addition to the reusability of the nanocomposites. The results showed that increasing content of Ni in Ni/Fe–Fe 3 O 4 nanocomposites, from 1 to 5 wt.%, greatly increased the dechlorination efficiency; the Ni/Fe–Fe 3 O 4 nanocomposites had much higher dechlorination efficiency than bare Ni/Fe nanoparticles . Ni content of 5 wt.% and initial pH below 6.0 was found to be the optimal conditions for the catalytic dechlorination of 2,4-DCP. Both 2,4-DCP and the intermediate product 2-chlorophenol (2-CP) were completely removed, and the concentration of the final product phenol was close to the theoretical phenol production from complete dechlorination of 20 mg/L of 2,4-DCP, after 3 hr reaction at initial pH value of 6.0, 3 g/L Ni/Fe-Fe 3 O 4 , 5 wt.% Ni content in the composite, and temperature of 22°C. 2,4-DCP dechlorination was enhanced by Cl − and inhibited by NO 3 − and SO 4 2 − . The nanocomposites were easily separated from the solution by an applied magnetic field. When the catalyst was reused, the removal efficiency of 2,4-DCP was almost 100% for the first seven uses, and gradually decreased to 75% in cycles 8–10. Therefore, the Ni/Fe–Fe 3 O 4 nanocomposites can be considered as a potentially effective tool for remediation of pollution by 2,4-DCP.
研究领域:
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Jun Hu,Zhiyong Huang,Jianming Yu
In this study, Fe/Fe 3 O 4 mixture was first applied as an additive to achieve the highly-effective mechanochemical destruction (MCD) of two halogenated organic pollutants (HOPs), hexachloroethane (HCE) and hexachlorobenzene (HCB). The MCD of HCE was more effective than that of HCB in virtue of the lower dissociation energy of C Cl bond. The MCD of HOPs occurred mainly via the reduction by Fe, Fe 3 O 4 and Fe/Fe 3 O 4 . The oxidation of Fe 3 O 4 and reduction of FeO (formed on account of the oxidation of Fe by oxygen-containing species) may also contribute to the HOP destruction. Fe/Fe 3 O 4 mixture exhibited a higher dechlorination rate (DR) than other three effective additives (i.e., Fe/SiO 2 , Al/Al 2 O 3 and Mg/Al 2 O 3 mixture), owing to the electrical property of Fe 3 O 4 and its electron transfer with Fe. The HOP destruction was significantly impacted by the mass fraction of Fe 3 O 4 (MF mag ) and achieved the maximum level with an MF mag of 70%. The DR of HOPs in the atmosphere of air was higher than those of pure oxygen and nitrogen because of the oxygen vacancy in Fe 3 O 4 and oxidation of Fe. The presence of water dramatically inhibited the HOP destruction due to the decrease of collision energy and its competition for the active sites in both Fe and Fe 3 O 4 . As expected, the DR of HOPs increased with rotation speed, and the mass ratio of ball to reactant and additive to pollutant. The analysis of intermediates indicates that HCB destruction was mainly via dechlorination and polymerization, while HCl cleavage also played an important role in HCE destruction. The results demonstrate that Fe/Fe 3 O 4 mixture is a suitable additive for MCD process.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2019
·
IF 0
Fu Chen,Hui Luo,Yongzhi Cheng,Jieling Liu,Xian Wang,Rongzhou Gong
Electromagnetic (EM) interference and radiation affecting human health and the operation of precision electronic devices have drawn considerable attention in recent years. Herein, a promising microwave-absorbing material, Ag nanoparticles (AgNPs)-decorated Fe/Fe3O4@N-doped carbon (NC) composite, was designed and fabricated with the Fe2O3@polydopamine@Ag hexagonal plates as the precursor. Crystalline structure, phase conversion, micromorphology, static magnetic properties, and EM characteristics of the samples were studied by various analytical techniques. The EM parameters of the obtained samples could be manipulated by increasing the pyrolysis temperature, exhibiting gradually enhanced dielectric and magnetic loss. Optimizing the coating thickness turns out to be a critical factor for regulating microwave absorption. The product obtained at 600 °C performs a maximum reflection loss (RL) value of −37.5 dB (10.64 GHz, 1.6 mm) and an effective absorption bandwidth (RL < −10 dB) up to 7.36 GHz (10.64–18 GHz) with a thickness of only 1.4 mm. In addition, the possible EM wave absorption mechanisms were further investigated in detail. In sum, it has been confirmed that the as-obtained AgNPs-decorated Fe/Fe3O4@NC composite with ultrabroad absorption bandwidths and strong absorption capacity would be an attractive candidate material for effective EM absorption materials in the future.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2022
·Vol. 169
·期 9
·097501
·
IF 4.386
Dongmei Ren,Xingwen Wang,Chunpeng Leng,Wei Meng,Jingrui Zhang,Chao Han
4-Nitrophenol (4-NP) is a typical organic pollutant, thus it is urgent to detect it in environmental samples. This study rationally designed a novel electrode material of P-doping Fe/Fe3O4@C (P-Fe/Fe3O4@C) prepared with MIL-88 as precursor. P2h-Fe/Fe3O4@C-700 was synthesized by calcining MIL-88 at 700 °C, followed by annealing process with NaH2PO2 for 2 h. The P2h-Fe/Fe3O4@C-700 modified glassy carbon electrode (P2h-Fe/Fe3O4@C-700/GCE) showed a high electrocatalytic activity toward 4-NP reduction due to its active metal center, fine-tuned electronic structure by P-doping, as well as good electrical conductivity. It exhibited excellent sensing behaviors in 4-NP detection with rather high sensitivities of 1415.43 μA·mM−1·cm−2 and 424.63 μA·mM−1·cm−2 in the 4-NP concentration of 5 to 100 μM and 100 to 1200 μM, respectively, with a low detection limit of 0.462 μM. The P2h-Fe/Fe3O4@C-700/GCE still had good selectivity for 4-NP detection in the presence of common interferences. In addition, it was found that the current response towards 4-NP at P2h-Fe/Fe3O4@C-700/GCE retained more than 97% of its initial value after one week, indicating a good long-term stability. Furthermore, the P2h-Fe/Fe3O4@C-700/GCE exhibited a good reproducibility. The constructed P2h-Fe/Fe3O4@C-700/GCE achieved practical uses for the sensing of 4-NP in tap water with satisfactory recoveries.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Junjie Su,Qi Yang,Zhihu Zhang,Ziyue Zhang
Nowadays, Ni/Fe bimetallic nanocomposites have shown great potential for removing Cr(VI). However, the action of Ni 0 in Cr(VI) removal is still controversial, which was studied in this work. In this study, Ni/Fe@Fe 3 O 4 -g-C 3 N 4 (NFFOCN) nanocomposites were applied to remove Cr(VI) from aqueous solutions and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and other methods. Batch experiments were conducted to evaluate the Cr(VI) removal performance. Experimental results demonstrated that under optimal operating conditions (pH 5.5, 10 mg/L Cr(VI), 0.3 g/L NFFOCN, 30°C), a Cr(VI) removal efficiency of 90.78% was achieved within 50 min. Theoretical maximum adsorption capacity was calculated to be 36.101 mg/g. Combining experimental and characterization results, it could be concluded that Cr(VI) removal was attributed to the synergistic effect of the NFFOCN components. Ni 0 not only participated directly in the reduction of Cr(VI) as an electron donor, but also converted the corrosion product H 2 of nano-zero-valent iron (nZVI) into highly reducible atomic hydrogen (·H) to remove Cr(VI). Additionally, Ni 0 could form a primary battery with nZVI, facilitating the electron transfer between nZVI and Cr(VI). NZVI and its derivatives, Fe 2+ ions and green rust, were responsible for Cr(VI) reduction. Furthermore, the presence of Fe 3 O 4 and carbon nitride (g-C 3 N 4 ) improved the stability and reactivity of the nanocomposites.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Mingliang Ma,Yuxin Bi,Zhengguo Jiao,Jiewei Yue,Zijian Liao,Yan Wang,Yong Ma,Weibo Huang
At present, the magnetic metal/carbon composites have been widely explored for microwave absorption (MA), which effectively integrate the characteristics of magnetic and dielectric materials . As a typical material, metal–organic framework (MOF) shows tremendous potential as a precursor or template. However, its development is limited by the inferior impedance matching. Herein, a novel rod-like Fe/Fe 3 O 4 /FeN/N-doped carbon (FON/NC) composite was synthesized via dual-ligand strategy and following calcination . The outer polypyrrole (PPy) shell, obtained by a facile polymerization method, effectively optimized the impedance matching and observably enhanced the MA capacity. Both the multi-component loss mechanism and unique porous core–shell structures of MOF-derived composites were beneficial for microwave attenuation . The effects of filler loadings (20 wt%, 25 wt%, 30 wt% and 35 wt%) on electromagnetic (EM) properties of FON/NC@PPy composites were discussed. Remarkably, as-obtained composites exhibited a minimum reflection loss (RL) value of −60.08 dB at the layer thickness of merely 1.44 mm and the widest effective absorption bandwidth (EAB, RL ≤ −10 dB) of 5.06 GHz at 1.64 mm with 30 wt% filler loading. This work provides a great reference for designing MOF-derived absorbers with high MA performance.
研究领域:
材料科学
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电磁学
✓ 已验证
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Shengyan Pu,Miaoting Wang,Kexin Wang,Yaqi Hou,Jing Yu,Qingqing Shi,Xiangjun Pei,Wei Chu
ABSTRACT As an effective and in situ purification strategy, adsorption technology has drawn much attention and recently the utilization of biomass substrate has been regarded as a promising way to enhance the adsorption performance and reduce cost. In this study, chitosan was applied as matrix and the magnetic Fe-crosslinked chitosan (CS-Fe@Fe 3 O 4 ) composite was obtained through a chelation procedure with cheap and environmentally friendly chitosan and iron salts. Then, the resultant CS-Fe@Fe 3 O 4 composites were characterized by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and thermogravimetric analysis. The sorption and desorption of methyl orange (MO), a common type of azo dye, on CS-Fe@Fe 3 O 4 composite was systematically studied to understand its availability for dyeing wastewater. The results revealed that CS-Fe@Fe 3 O 4 composites could efficiently remove MO in a wide pH range. The mixed Fe 3 O 4 particles were physically mixed andalmost had no negative effect on its adsorption. Moreover, the dye adsorption process was found to be controlled by the pseudo-second-order rate model and the adsorption isotherm behavior could be described by the Langmuir model. The repeatability test showed that the CS-Fe@Fe 3 O 4 composites could retain its high efficiency after desorption and regeneration. In summary, the results presented herein indicated that the resultant CS-Fe@Fe 3 O 4 nanocomposite with high adsorption efficiency and strong magnetic property could serve as a potential adsorbent for remediating industrial dyeing wastewater.
研究领域:
环境科学
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材料科学
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水处理
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Gang Li,Ruiyang Tan,Bohong Gao,Xinli Liu,Mingyuan Zhang,Ping Chen,Xinyi Wang
Developing advanced electromagnetic wave absorption (EMWA) materials is crucial for curbing electromagnetic pollution. This study presents the synthesis of core–shell Fe/Fe 3 O 4 /C composites, FFC-700 and FFC-800, derived from Prussian blue@covalent organic framework (PB@COF) via pyrolysis at 700 and 800 °C, and the hollow FFC-900 at 900 °C. Their chemical compositions, microstructures, and EMWA performances were thoroughly examined. FFC-700 and FFC-800, featuring core–shell structures and abundant interfaces, facilitate electron transfer and enhance polarization effects. Notably, FFC-700 achieved a minimum reflection loss (RL min ) of − 75.82 dB at an ultrathin thickness of 1.45 mm, with an effective absorption bandwidth (EAB) of 6.22 GHz at 1.66 mm, spanning the entire Ku-band. FFC-800 also provides substantial EMWA performance, with an RL min of − 30.14 dB at 1.61 mm and an EAB of 6.08 GHz at 1.67 mm, also covering the Ku-band. Radar cross-section (RCS) simulations reveal the absorbers’ exceptional radar stealth, with their coatings significantly reducing RCS values. The composites’ adjustable structure, balanced composition, and dielectric-magnetic synergy optimize impedance matching for full-Ku-band coverage. This work offers a promising approach to fabricating efficient EMWA materials from PBA@COF and MOF@COF precursors.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2015
·
IF 4.504
Dekang Huang,Yanping Luo,Shaohui Li,Mingkui Wang,Yan Shen
To realize a large-scale application of fuel cells, it is highly desirable to develop noble metal-free electrocatalysts for oxygen reduction reaction (ORR). Herein, a highly active electrocatalyst is synthesized by impregnating in situ generated iron(III)-1,10-phenanthroline complex on commercially high specific surface area carbon blacks and subsequent pyrolysis at high temperature. High ORR limiting current density (5.79 mA cm −2 ) and positive half-wave potential (0.859 V versus RHE) over this electrocatalyst with a mass loading of 0.2 mg cm −2 can be achieved in 0.1 M KOH solution, which are very comparable with the benchmark Pt/C electrocatalyst. Detailed investigations have revealed the existence of nitrogen doped carbon (N-C), nitrogen coordinated to Fe (Fe-N), and Fe@Fe 3 O 4 core-shell nanoparticles in this composite electrocatalyst. The high activity of this electrocatalyst is attributed to the synergistic effect among them.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Caiyu Ge,Yuefan Wang,Yilin Wang,Zhifang Liu,Chao Chen,Yixi Xie,Pengcheng Zhao,Junjie Fei
As a natural flavonoid compound found in fruits, vegetables and herbs, luteolin (LU) has potent pharmacological activities and beneficial biological properties. Here, a Fe/Zn bimetallic ZIF pyrolysis-derived Fe-Fe 3 O 4 N-doped mesoporous carbon was in-situ grown on carbon nanofibers (Fe-Fe 3 O 4 -NPC@CNFs), and it was used as an ultrasensitive electrochemical sensing platform for the efficient detection of LU in natural samples. Multiple characterization results show that Fe-Fe 3 O 4 -NPC@CNFs is a dodecahedral particle uniformly grown on CNFs with good crystal structure and uniform elemental distribution. Its rough surface with good mesoporous structure and high specific surface area of 823.19 m 2 /g is beneficial for LU adsorption. The density of states (DOS) and adsorption energies of NPC and Fe-Fe 3 O 4 -NPC further demonstrate that Fe-Fe 3 O 4 -NPC has better electrochemical performance and adsorption effect on LU. Under optimized conditions (carbonization: 800℃, pH: 5.0, enrichment: −0.2 V for 400 s), the Fe-Fe 3 O 4 -NPC@CNFs/GCE sensor showed satisfactory detection performance for LU in the range of 0.001–1.5 μM with the limit of detection (LOD) of 0.47 nM. Furthermore, this sensor exhibits excellent anti-interference capability, reproducibility, and stability, and it was also possible to effectively detect LU in food samples. This work provides a new strategy for the quantitative analysis of LU in food.
研究领域:
分析化学
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材料科学
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电化学
·
纳米技术
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食品科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2015
·Vol. 3
·期 39
·10232-10241
·
IF 4.696
Hualiang Lv,Guangbin Ji,Wei Liu,Haiqian Zhang,Youwei Du
Hierarchical hollow carbon@Fe@Fe3O4 nanospheres were synthesized by a simple template method and another pyrolysis process. Interestingly, the thickness of hollow carbon spheres is tunable by a simple hydrothermal approach. The as-prepared carbon@Fe@Fe3O4 shows excellent microwave absorption properties. In detail, the maximum effective frequency is up to 5.2 GHz with an optimal reflection loss value of −40 dB while the coating thickness is just 1.5 mm. Meanwhile, such absorption properties can be maintained via controlling the thickness of the hollow carbon. For instance, in another coating layer of 2 mm, the effective frequency is still more than 5 GHz as the carbon thickness declines to 12 nm. As novel electromagnetic absorbers, the composites also present the lower density feature due to the hollow carbon sphere frame. The excellent electromagnetic absorption mechanism may be attributed to the obvious interface polarization, and strong magnetic loss ability resulting from the Fe and Fe3O4 shell. Besides, owing to the dielectric feature of carbon, the hollow carbon core is beneficial for the attenuation ability.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
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