WATER SCIENCE AND TECHNOLOGY
·
2020
·Vol. 82
·期 2
·242-254
·
IF 1.638
Wang Jinpeng,Zhang Ming,Zhou Runjuan,Li Jiyuan,Zhao Wei,Zhou Jinghong
Using waste pomelo peel as raw material, pomelo peel-based biochar (BC) was prepared by pyrolysis at 400 °C, and the pomelo peel-based biochar was prepared by loading γ -Fe 2 O 3 onto the surface of the pomelo peel-based biochar by unlimited oxygen chemical precipitation. The results showed that the pomelo peel biochar loaded with γ -Fe 2 O 3 had higher specific surface area and larger pore volume. The load of γ -Fe 2 O 3 gives γ -Fe 2 O 3 @BC excellent magnetic separation ability, and its magnetic saturation intensity is as high as 30.60 emu/g. BC and γ -Fe 2 O 3 @BC were applied to remove norfloxacin (NOR) from a water body. It was found that the adsorption of NOR by both of them followed the pseudo-second-order kinetic model. The adsorption isotherm mainly conforms to the Sips model, and the adsorption process of NOR is a spontaneous endothermic reaction. The pH and ionic strength have a great influence on the adsorption of NOR by BC and γ -Fe 2 O 3 @BC, and they play a role mainly by influencing the morphology of NOR in water. The adsorption mechanism showed that cation exchange and hydrogen bonding were the main forces for BC to adsorb NOR. Moreover, the γ -Fe 2 O 3 particles enhanced the hydrophobicity of the pomelo peel-based biochar, making the hydrophobicity become the main force for the adsorption of NOR by the γ -Fe 2 O 3 @BC. The adsorption–desorption experiment showed that after four cycles of recycling, the adsorption capacity of γ -Fe 2 O 3 @BC for NOR was still up to 61.43% of the initial adsorption capacity, and it had a good recycling property.
研究领域:
环境科学
·
材料科学
·
水污染控制
·
环境功能材料
·
吸附化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Xianfa Zhang,Mingzhao Huang,Zuoming Zhou,Xiaodan Zhao,Guohua Jing
Sulfite activation with iron-based heterogeneous activators is a promising technology for the removal of organic contaminants from water. However, the slow valence transformation of >Fe(II)/>Fe(III) compromises sulfite activation efficiency. Regarding that the oxygen vacancy (Vo) can modulate the charge distribution and thus enhance >Fe(II)/>Fe(III) valence transformation via rapid electron transfer, Vo-enriched γ-Fe 2 O 3 is constructed for sulfite activation (simplified as the γ-Fe 2 O 3 -Vo/sulfite system). The γ-Fe 2 O 3 -Vo/sulfite system exhibits excellent abatement performance for iohexol (IOX) with the efficiency as high as 90.2 % within 1 h of reaction at pH 8.5, in which sulfate radicals (SO 4 •− ) and hydroxyl radicals (HO • ) are the major species. Electrochemical and DFT calculations reveal that Vo-enriched γ-Fe 2 O 3 possesses lower electrical impedance and the concomitant higher electron transfer efficiency. According to a series of characterizations, the enhance >Fe(II)/>Fe(III) valence transformation is confirmed to contribute to sulfite activation via the regulation of the electronic structure by the Vo. In addition, the degradation pathways of IOX are proposed by analyzing the degradation products of IOX by UPLC-QTOF-MS. Finally, the effects of different influencing factors on the degradation of IOX and the cyclic performance suggest the system shows strong resistance to interference and reusability, exhibiting superior application potential.
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
Materials
·
2024
·Vol. 17
·期 7
·1501
·
IF 3.1
Xiaohai Wang,Zhuanzhuan Shi,Zhikai Wang,Xiaoshuai Wu
The microbial hybrid system modified by magnetic nanomaterials can enhance the interfacial electron transfer and energy conversion under the stimulation of a magnetic field. However, the bioelectrocatalytic performance of a hybrid system still needs to be improved, and the mechanism of magnetic field-induced bioelectrocatalytic enhancements is still unclear. In this work, γ-Fe2O3magnetic nanoparticles were coated on aShewanella putrefaciensCN32 cell surface and followed by placing in an electromagnetic field. The results showed that the electromagnetic field can greatly boost the extracellular electron transfer, and the oxidation peak current of CN32@γ-Fe2O3increased to 2.24 times under an electromagnetic field. The enhancement mechanism is mainly due to the fact that the surface modified microorganism provides an elevated contact area for the high microbial catalytic activity of the outer cell membrane’s cytochrome, while the magnetic nanoparticles provide a networked interface between the cytoplasm and the outer membrane for boosting the fast multidimensional electron transport path in the magnetic field. This work sheds fresh scientific light on the rational design of magnetic-field-coupled electroactive microorganisms and the fundamentals of an optimal interfacial structure for a fast electron transfer process toward an efficient bioenergy conversion.
研究领域:
微生物学
·
生物能源
·
纳米生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2024
·
IF 7.6
Qian Xu,Qian Xue,Shengmei Tan,Zhiliang Cheng,Xueqiang Qi,Chaoqun Yan
A low band gap and visible light-responsive heterogeneous Photo-Fenton catalyst of γ-Fe 2 O 3 /CQDs micron composite was prepared under the one-pot hydrothermal method. The Photo-Fenton degradation of γ-Fe 2 O 3 /CQDs towards dye solution of rhodamine B(RhB), methyl blue (MB), and methyl orange (MO) was studied comparatively with α-Fe 2 O 3 . The γ-Fe 2 O 3 /CQDs exhibited remarkable catalytic performance for various dyes and with a first-order rate ( k ) of 14 times higher than that of initial α-Fe 2 O 3 with a low concentration of H 2 O 2 of 0.049 mmol . L −1 and a wider pH range of 3.1–7.1. The microstructure of the compounds was observed by XRD, SEM, TEM, FT-IR, and XPS characterization results suggested that the γ-Fe 2 O 3 /CQDs nanocomposite was formed through the stable Fe–O–C bonds, thus, the band gap decreased, and it is more favorable for the distance of holes and electrons. The free radical trapping experiment and EPR analysis indicated that •OH and 1 O 2 were the major active species during the typical photo-Fenton reaction. What's more, the γ-Fe 2 O 3 /CQDs also exhibited good stability and magnetic properties. DFT conclusion shows that the mechanism of the potential determination step (PDS) on α-Fe 2 O 3 (220) is the cleavage of H 2 O 2 with an energy barrier of only 0.08 eV, which is 0.54 eV lower than that of OH* on γ-Fe 2 O 3 (220). Thus it can be deemed that γ-Fe 2 O 3 /CQDs perform much higher catalytic activity for the dissociation of H 2 O 2 than α-Fe 2 O 3 . This work gives a feasible and economical countermeasure of visible light Photo-Fenton dispose of dye wastewater with a recyclable magnetic γ-Fe 2 O 3 /CQDs micron catalyst.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhihui Yao,Yuting Li,Daisong Chen,Yiwen Zhang,Xinghong Bao,Juan Wang,Qin Zhong
Carbon-based materials have shown promising results in replacing commercial Pt/C as highly efficient oxygen reduction reaction (ORR) catalysts in renewable energy devices. Designing unique structures of carbon matrix and introducing more active sites are essential for their application as electrode materials. Herein, a feasible approach is reported to synthesize dispersive γ -Fe 2 O 3 clusters embedded in 1D porous carbon nanofibers (CNFs) ( γ -Fe 2 O 3 @CNFs-12) through electrospinning, impregnation and pyrolysis processes. The resulted γ -Fe 2 O 3 @CNFs-12 exhibits excellent ORR performance in alkaline electrolyte with a surprising half-wave potential ( E 1/2 ) of 0.905 V and merely 5 mV drop of the potential after 5000 cycles, outperforming that of commercial Pt/C. Meanwhile, it also shows considerable ORR performance in acidic and neutral media. The remarkable ORR catalytic activity and durability are primarily attributable to the well-designed 1D hierarchical porous structure and accessible γ -Fe 2 O 3 clusters that embedded in carbon nanofibers. γ -Fe 2 O 3 @CNFs-12 is also capable to act as an air cathode for Zn-air batteries with an open circuit voltage of 1.428 V. This work provides a new perspective to the novel design and synthesis of carbon-based ORR electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 18
·10272-10281
·
IF 3.049
Yide Xia,Ying Liu,Nannan Shi,Xungao Zhang
In this article, the catalyst Au/γ-Fe2O3@hydroxyapatite (Au/γ-Fe2O3@HAP) consisting of Au nanoparticles supported on the core–shell structure γ-Fe2O3@HAP was prepared through a deposition–precipitation method. The catalyst was characterized by transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, N2 adsorption–desorption and atomic absorption spectrometry. The as-prepared Au/γ-Fe2O3@HAP exhibited excellent performance for the reduction of 4-nitrophenolate (4-NP) to 4-aminophenolate (4-AP) in the presence of NaBH4 at room temperature. Thermodynamic and kinetic data on the reduction of 4-NP to 4-AP catalyzed by the as-prepared catalyst were studied. The as-prepared catalyst could be easily separated by a magnet and recycled 6 times with over 92% conversion of 4-NP to 4-AP. In addition, the as-prepared catalyst showed excellent catalytic performance on other nitrophenolates. The TOF value of this work on the reduction of 4-NP to 4-AP was 241.3 h−1. Au/γ-Fe2O3@HAP might have a promising potential application on the production of 4-AP and its derivatives.
研究领域:
材料科学
·
化学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 7
·1-8
·
IF 6.232
Li Nianlu,Li Ruohan,Song Yinshuang,Ma Long,Gao Cuiling,Li Lili,Cheng Shi-Bo,Zhang Xiaoli,Chen Jing,Zhan Jinhua
Carbonaceous shell-coated γ-Fe 2 O 3 nanoparticles (γ-Fe 2 O 3 @CNM) were synthesized from glucose caramelization and used as a novel magnetic solid-phase extraction medium for malachite green and crystal violet in environmental water. Malachite green and crystal violet were absorbed on to γ-Fe 2 O 3 @CNM by electrostatic and π-interactions. The morphologies, pore structures, surface functional groups, and magnetic properties of γ-Fe 2 O 3 @CNM were characterized by TEM, FTIR, hysteresis regression, Brunauer-Emmet-Teller analysis, zeta potential, XPS, and XRD. The magnetic solid-phase extraction procedure was optimized by extraction pH, absorption time, desorption solvent, and desorption time. The absorption capacities (q max values) for malachite green and crystal violet were 34.2 and 27.9 mg g −1 , respectively. After magnetic solid-phase extraction, malachite green and crystal violet were determined by LC-MS/MS. The analytical method was validated with a linear range of 0.02–20 ng mL −1 , enrichment factor of 25.8 and 25.4, method detection limit of 0.004 ng mL −1 , and intra-day precisions of 2.1% and 2.6% for malachite green and crystal violet, respectively. The relative recovery was found to be 73.4–101.5% for malachite green and 83.1–102.7% for crystal violet upon the application of the magnetic solid-phase extraction method to real water samples from lake, spring, sea, fishpond, and industrial waste.
Caramelized-carbon-coated magnetic nanoparticles are used as novel extraction medium based on electrostatic and π-interactions. It is porous, amphiphilic, electronegative, magnetically strong, and features abundant absorption site. These characteristics stimulate mass transfer and result in a useful MSPE method in environmental analysis.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 7
·期 1
·336-343
·
IF 3.289
Tao Chen,Yuhao Xiong,Yuemei Qin,Haiguan Yang,Peng Zhang,Fanggui Ye
In this study, a novel and low-cost method was developed for synthesizing magnetic porous γ-Fe2O3/C as an adsorbent and catalyst for removal of methylene blue (MB) from aqueous solution. Using FeCl3·6H2O and bagasse as the precursor, the biomass-based material was synthesized rapidly using a microwave heating process. Fe ions were introduced to achieve both adsorption and catalytic degradation by the Fenton reaction. Characterization by BET, XRD, SEM, and TEM indicated that the prepared γ-Fe2O3/C material exhibited homogeneous mesoporosity with a BET surface area, mesoporous volume, and saturation magnetization of 764.116 m2 g−1, 0.54 cm3 g−1, and 17.1 emu g−1, respectively. The material exhibited excellent adsorption and catalytic degradation abilities for removal of MB from aqueous solution (up to 352.96 mg g−1), with complete degradation of MB within 30 min. Moreover, γ-Fe2O3/C had good stability over 5 cycles. Therefore, this biomass-based γ-Fe2O3/C material can be used as a highly effective and low-cost adsorbent and catalyst and has great potential application in clean-up processes for environmental pollutants.
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 APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Miaotian Long,Zerui Zhang,Long Yan,Liang Yi
For effectively strengthening the comprehensive properties of intumescent flame-retardant epoxy resins (EPs), a microencapsulating γ-Fe 2 O 3 by polypyrrole (PPy) named PPy-Fe 2 O 3 was synthesized and used as a synergist to simultaneously enhance the flame retardancy, smoke toxicity suppression and mechanical strength of EP composites containing diaminodiphenylmethane modified ammonium polyphosphate (DDP). The results demonstrate that the mixture of PPy-Fe 2 O 3 and DDP exhibits a surprising synergistic effect on strengthening the comprehensive properties of EP composites. Specifically, EP composite containing 0.2 wt% PPy-Fe 2 O 3 and 9.8 wt% DDP achieves the UL94 V-0 rating with a limiting oxygen index (LOI) value of 35.5%, while 10 wt% DDP only imparts a UL94 V-1 rating and a LOI value of 34.0% to EP. Furthermore, 0.2 wt% PPy-Fe 2 O 3 shows a 11.0% reduction in peak smoke production rate and a 12.3% reduction in peak heat release rate of the EP/DDP system. The enhanced fire security of EP/DDP/PPy-Fe 2 O 3 is attributed to the formation of more phosphorus-rich structures retained in the char, thus reducing the release of harmful gases including NH 3 , CO, and CO 2 , and generating more incombustible gases including H 2 O to weaken burning intensity. Meanwhile, the satisfactory compatibility of PPy-Fe 2 O 3 with epoxy matrix imparts a superior mechanical strength to EP composites.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale Advances
·
2022
·Vol. 4
·期 5
·1414-1421
·
IF 5.598
Hui Zhang,Jianping Zhang,Yi Chen,Tianze Wu,Mingzhu Lu,Zhenxia Chen,Yu Jia,Yongtai Yang,Yun Ling,Yaming Zhou
The size modulation of hollow carbon nanospheres (HCSs) has attracted great interest in the contexts of cellular uptake, drug delivery and bioimaging. In this study, a facile fabrication method was specifically used to minimize all influencing factors except for the particle size. A series of nanoparticles of hollow carbon nanospheres embedded with magnetic resonance imaging (MRI) nanoagent γ-Fe2O3 and GdPO4 nanoparticles (Fe–Gd/HCS), were successfully prepared and applied to in vitro/vivo evaluation with well-defined sizes of ∼100 nm (Fe–Gd/HCS-S), ∼200 nm (Fe–Gd/HCS-M), and ∼300 nm (Fe–Gd/HCS-L), respectively. Then the in vitro size effect of Fe–Gd/HCS was systematically investigated by bio-TEM, CLSM, CCK-8 assay, and flow cytometry revealing that Fe–Gd/HCS could be internalized and the cellular uptake amounts increase with the decrease of size. Furthermore, the in vivo size-effect behavior of Fe–Gd/HCS (∼100 nm, ∼200 nm, ∼300 nm) was tracked by MRI technique, demonstrating that all Fe–Gd/HCS can distinguish the liver, in which Fe–Gd/HCS with the smallest particle size exhibited the best performance among these nanoparticles. By leveraging on these features, Fe–Gd/HCS-S (∼100 nm) was further chosen as a theranostic agent, preliminarily presenting its capability for multi-modal imaging and therapy.
研究领域:
纳米医学
·
生物材料
·
医学影像学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2013
·Vol. 15
·期 21
·8228-8236
·
IF 3.829
Shaofeng Zhang,Feng Ren,Wei Wu,Juan Zhou,Xiangheng Xiao,Lingling Sun,Ying Liu,Changzhong Jiang
Composite materials containing different components with well-defined structures may cooperatively enhance their performance and extend their applications. In this work, core–shell γ-Fe2O3@SnO2 hollow nanoparticles (NPs) were synthesized by a low-cost and environmentally friendly seed-mediated hydrothermal method. Firstly, the γ-Fe2O3 hollow NPs were synthesized by a template-free method. Then they were used as the cores for the growth of SnO2 shells. The thickness of the shell can be simply tailored by controlling the reaction time. Various techniques, including SEM, XRD, TEM and HRTEM, were employed to investigate the morphology, structure and formation process of the special core–shell hollow structures. The combination of magnetic semiconductor (γ-Fe2O3) and wide band-gap semiconductor (SnO2) endowed them with great potential to be used as recyclable photocatalysts. Experiments on photo-degradation of Rhodamin B (RhB) dye in the presence of the samples showed that the hybrid structures possessed higher photocatalytic activities than the monomer structures of SnO2 and γ-Fe2O3 materials indicating a strong coupling enhancement effect between the wide and narrow band-gap semiconductors. Moreover, the gas sensing tests of the γ-Fe2O3@SnO2 hollow NPs revealed that the samples exhibited fast response and recovery rates, which enable them to be promising materials for gas sensors.
研究领域:
材料科学
·
环境科学
·
纳米技术
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Yuting Yan,Yuhang Ge,Hanping Mao,Qirui Wang,Qinglin Li,Henan Li
The development of an innovative peroxidase mimic is crucial for achieving accurate and low-cost naked-eye detection for pesticide residues in agricultural products. Herein, a visual sensor for chlorpyrifos was engineered by employing γ-Fe 2 O 3 /thiophene-sulfur-doped graphene (γ-Fe 2 O 3 /t-SG) magnetic nanocomposite as an artificial nanozyme . The γ-Fe 2 O 3 /t-SG magnetic nanocomposite with single–crystalline structure was fabricated by a facile thermal-treatment strategy by controlling the annealing temperature between graphene oxide (GO) and ferric sulfate. Significantly, the resulting γ-Fe 2 O 3 /t-SG magnetic nanocomposite revealed the markable peroxidase-like activity toward 3,3,5,5-tetramethyl benzidine oxidation (TMB). A novel colorimetric method for the rapid detection of chlorpyrifos was developed based on the high enzyme-like activity of γ-Fe 2 O 3 /t-SG magnetic nanocomposite and the inhibition of acetylcholinesterase activity by chlorpyrifos. This colorimetric sensor demonstrated excellent performance in chlorpyrifos quantification, with a linear range from 0.5 to 1000 μg mL −1 and a detection limit of 0.17 μg mL −1 (S/N = 3). The stability, ease of separation, and high peroxidase-like catalytic activity of γ-Fe 2 O 3 /t-SG magnetic nanocomposite makes it as an ideal candidate for a wide range of potential applications as peroxidase mimetics.
研究领域:
分析化学
·
环境科学
·
农业科学
✓ 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）