ENVIRONMENTAL POLLUTION
·
2020
·
IF 6.793
Mengjie Hao,Pan Gao,Dian Yang,Xuanjin Chen,Feng Xiao,Shaoxia Yang
The emergence of organophosphorus flame retardants and the efficient removal from aquatic environments have aroused increasing concerns. The Urea functionalized Fe 3 O 4 @LDH (Urea-Fe 3 O 4 @LDH) was prepared and used to adsorb triphenyl phosphate (tphp) for the first time. The tphp adsorption capacity was up to 589 mg g −1 , and the adsorption rate reached 49.9 mg g −1 min −1 . Moreover, the influences of various environmental factors (pH, ionic strength and organic matter) on the tphp adsorption on the Urea-Fe 3 O 4 @LDH were investigated. The initial pH of the solution significantly affected the tphp adsorption, whereas the ionic strength and HA slightly affected the adsorption. The main adsorption mechanism was attributed to electrostatic interaction and π-π interaction. We believe that urea is one of excellent functional groups for the tphp adsorption removal and the materials with urea groups as the adsorbents exhibit good prospects in the future.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Guangchao Sun,Jiayu Zhang,Xiang Li,Bianlei Hao,Fatang Xu,Kaiqi Liu
The efficient removal of Cr(VI) in water with high solubility and mobility is of great significance because Cr(VI) is one of the most toxic heavy metals, but it also faces some major challenges. The dispersibility and recyclability of nanoadsorbents are closely related to their Cr(VI) removal efficiency. Herein, the self-assembly method was used to synthesize core-shell hybrid nanoparticles , named Fe 3 O 4 @LDH, with a vertically aligned layered double hydroxide (MgAl-LDH) nanosheet shell and a Fe 3 O 4 magnetite core. The obtained Fe 3 O 4 @LDH nanoparticles exhibit a highly porous and well-ordered three-dimensional core-shell structure with a wool-ball-like morphology. The self-assembled morphology of the core-shell structure can be effectively controlled and induced by regulating the Mg 2+ /Al 3+ ratio of the reaction system. The influence mechanism of charge density of LDH brucite-like layers on the self-assembled morphology was proposed. Fe 3 O 4 @LDH nanoparticles exhibit a Cr(VI) adsorption capacity of 108.7 mg/g. The synergetic contribution of the hybrid self-assembly of Fe 3 O 4 and MgAl-LDH leads to more dispersion, better adsorption capability, and faster kinetics. Moreover, because of the super-paramagnetic and highly saturated magnetization (34.53 emu/g) of the Fe 3 O 4 @LDH nanoparticles, they can be used as efficient magnetic adsorbents and easily separated using a magnetic field and reused. The prepared Fe 3 O 4 @LDH nanoparticles are a cost-effective nanoadsorbent for removing Cr(VI) from wastewater and provide a reference for the structural design and construction of nanocomposites .
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2023
·
IF 6.2
Shijun Nie,Juan Wu,Lan Wang,Fan Cheng,Zhengguang Sun,Xiaobo Chen,Hai Liu,Sheng Wen,Chunli Gong
The trade-off between ionic conductivity and mechanical properties is the key issue facing anion exchange membranes (AEMs) at present. Herein, a new strategy combing three-dimensional (3D) hierarchical nanoarchitecture and magnetic field orientation was proposed to prepare imidazolium-functionalized poly(2,6-dimethyl phenylene oxide) (ImPPO)-based composite AEMs with simultaneously improved ionic conductivity and mechanical strength. Magnetic Fe 3 O 4 @LDH microspheres using Fe 3 O 4 as the core and two-dimensional lamellar anion conductor, layered double hydroxide (LDH), as the shell were prepared through a simple co-precipitation method. The as-prepared Fe 3 O 4 @LDH was then incorporated into ImPPO matrix and induced by an external magnetic field to fabricate Fe 3 O 4 @LDH-orientated composite AEMs. The hierarchical-structured Fe 3 O 4 @LDH can not only effectively avoid the stacking of LDH laminates and thus fully play the ion conduction ability of LDH, but also contribute to the formation of continuous OH − ion transport pathway in the composite system after magnetic field induction. The magnetic-field-oriented membrane with 1% Fe 3 O 4 @LDH doping exhibited ionic conductivity of 128.9 mS cm −1 at 80 °C, which was 43.1% higher than that of pure ImPPO. Moreover, the high dry strength (30.7 MPa) and satisfactory wet strength and flexibility of the composite membrane were also obtained. The assembled direct methanol fuel cell demonstrated a peak power density of 11.7 mW cm −2 , and showed an OCV retention of as high as 94.7% after continuous operation for 100 h, indicating their great potential for fuel cell applications.
研究领域:
材料科学
·
燃料电池工程
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2017
·Vol. 35
·期 7
·1149-1156
·
IF 1.852
Xuejia Gao,Libo Niu,Xianliang Qiao,Wenhui Feng,Yingying Cao,Guoyi Bai
A novel NiB deposited layered double hydroxide (LDH) coated ferroferric oxide (Fe 3 O 4 @LDH@NiB) magnetic core-shell nanocomposite was successfully fabricated by the combination of coprecipitation and impregnation-reduction. During the Fe 3 O 4 @LDH preparation, a facile template-free approach was employed to introduce the LDH shell, which was more efficient than the conventional method for the preparation of mesoporous materials that always needs to introduce and remove templates. The resulted Fe 3 O 4 @LDH has a relatively high surface area and abundant surface hydroxyl group, which can adsorb metal ions, making it favorable to disperse and stabilize the active Ni species, as demonstraed by TEM, XPS, FT-IR and BET characterizations. Therefore, it exhibited good activity in the selective hydrogenation of cinnamic acid to hydrocinnamic acid with the conversion and selectivity both approaching to 100%. Notably, the obtained Fe 3 O 4 @LDH@NiB can be easily separated by an external magnetic field and recycled eleven times without appreciable loss of its initial catalytic activity.
研究领域:
材料化学
·
纳米催化
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绿色化学
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应用化学
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功能材料
✓ 已验证
DOI
高影响因子
APPLIED CLAY SCIENCE
·
2019
·
IF 3.89
Shifeng Zhao,Mi Wu,Ruisen Jing,Xijuan Liu,Yifei Shao,Qian Zhang,Fengzhu Lv,Aiju Liu,Zilin Meng
Magnetic ZnAl-LDH composite materials (Fe 3 O 4 @LDH) based on the electrostatic attraction was manufactured by self-assembly method to remove Cr(VI) from wastewater simultaneously. Fe 3 O 4 microspheres with suitable size can be surrounded by the LDH layers in the formation process to separate easily and reduce the dosage of Fe 3 O 4 . The removal behaviors of Cr(VI) from wastewater were investigated and the obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopic (TEM) and molecular simulation. Equilibrium studies indicated that the experimental data was well described by Langmuir models and the removal was a charge-limited process. Compared with other reported papers, the removal capacity for Cr(VI) by this method was larger, revealing a maximum utilization of charges on LDH. By molecular simulation, the relationship among chemical bond, electron transfer and energy was explained microscopically and the removal mechanism was proved that Cr(VI) trapped onto Fe 3 O 4 @LDH involved ion electrostatic interaction. The reusability of Fe 3 O 4 @LDH composite was tested and illustrated that it can be reused for several times.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ORGANOMETALLIC CHEMISTRY
·
2018
·
IF 1.946
Jin Li,Yajuan Wang,Shunwang Jiang,Hui Zhang
A series of novel magnetic recyclable Pd Au nanoclusters (NCs) catalysts x-PdAu r /Fe 3 O 4 @LDH (x: Pd loading in wt%, r: Au/Pd molar ratio, LDH : layered double hydroxide, here refers the typical MgAl-LDH) were synthesized by a facile polyol reduction followed sol immobilization of PdAu r –PVP on core@shell support Fe 3 O 4 @LDH. Systematic characterizations reveal that the obtained catalysts possess the honeycomb-like core@shell, and the ultrafine PdAu alloy nanoclusters with the size in 1.70–2.55 nm highly dispersed on the LDH nanoplates shell. The obtained catalysts 1.0-PdAu r /Fe 3 O 4 @LDH (r: 0.11, 0.16 and 0.48) show higher Heck activity of iodobenzene with styrene than monomentallic ones, especially 1.0-PdAu 0.16 /Fe 3 O 4 @LDH displays the highest Heck activity under the optimal condition. Moreover, the catalysts can be applied for the Heck reaction of a variety of aryl halides with alkenes , and can be conveniently separated by an external magnet and reused ten runs without significant loss of activity.
研究领域:
化学
·
催化材料
✓ 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）