JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Kefa Sheng,Hongyu Xia,Jianping Ge
Selective hydrogenation of nitroaromatics is a crucial industrial reaction, but there are still challenges in developing nanocatalysts with stable active centers, yet easily recyclable characteristics. Here, a magnetically separable Pd/Fe 3 O 4 @SiO 2 nanocatalyst was prepared through the seeding growth of silica on the Fe 3 O 4 nanocrystal cluster (NC) followed by in situ reduction of Pd nanoparticles (NPs) on the amino group modified Fe 3 O 4 @SiO 2 nannotube (NT). The nanocatalyst showed good activity and stability in the hydrogenation of a series of nitroaromatics as the Pd NPs were highly dispersed on the nanotubes. Meanwhile, it could be easily separated from the reaction solution and well-redispersed in the solvent for the next-round reaction due to the superparamagnetic property of the Fe 3 O 4 NC and the good dispersibility of silica in many organic solvents. The magnetically separable nanocatalyst combined the high activity of the nanocatalyst and the convenient separation of a traditional heterogeneous catalyst, which effectively promote the practical application of nanomaterials in catalysis.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Jie Min,Wei Song,Tianding Hu,Yunfei Zhi,Zhenhao Xia,Tiecheng Zhang,Shaoyun Shan,Hongying Su
Magnetic nanoparticle-supported heterogeneous catalysts have been widely researched in green catalysis, due to their convenient magnetic separation and nanometer effects. Herein, a magnetic Co(III)-Salen heterogeneous catalyst with uniform spherical core-shell structure was synthesized for the chemical fixation of CO 2 into cyclic carbonate based on the sustainable protocol development and green chemistry principles. Fe 3 O 4 @SiO 2 nanoparticles with uniform spherical core-shell structure were prepared by the reverse microemulsion method, and Co(III)-Salen complexes were subsequently immobilized on the resulted Fe 3 O 4 @SiO 2 nanoparticles via covalent bonding, leading to Fe 3 O 4 @SiO 2 @Co(III)-Salen nanocomposites with particle size of 29 nm and saturation magnetization value of 27.2 emu/g. The catalytic performance study indicated that the catalyst exhibited high yield of 99% with selectivity of 100% for the ring-opening addition reaction of CO 2 and epoxide under solvent-free reaction condition. A plausible reaction mechanism was proposed that the Lewis acidic sites of Co(III)-Salen and nucleophilic bromine ion components played synergetic roles in promoting cycloaddition reactions. A stable geometry of the Co(III)-Salen complex and a detailed evidence for the reaction mechanism were provided by the density functional theory (DFT) calculations. Based on their excellent magnetic properties , the Co(III)-Salen nanocomposites could be easily recovered by using an external magnet and reused for 5 times without significant leaching of metal center and loss of catalytic activity.
研究领域:
材料科学
·
绿色化学
·
催化反应
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2013
·
IF 2.112
Yaohui Xu,Yang Zhou,Wenhui Ma,Shixing Wang,Shaoyuan Li
The Fe 3 O 4 nanoparticles [NPs] coated with silica nanoparticles were designed to produce magnetic core–shell Fe 3 O 4 @SiO 2 NPs, which were modified with rhodamine B derivatives and defined as Fe 3 O 4 @SiO 2 -Rho NPs. The obtained Fe 3 O 4 @SiO 2 -Rho NPs served as a fluorescent OFF-ON nanosensor was utilized to detect Zn 2+ selectively in acetonitrile medium. The Fe 3 O 4 @SiO 2 -Rho NPs exhibited selective “turn-on” type fluorescent enhancements and distinct color changes with Zn 2+ . The Fe 3 O 4 @SiO 2 -Rho NPs also showed a high capacity for removal of Zn 2+ at room temperature. The removal efficiency toward Zn 2+ was about 87.34%. In addition, the presence of magnetic Fe 3 O 4 particles as core in Fe 3 O 4 @SiO 2 -Rho NPs could facilitate the magnetic separation of the Fe 3 O 4 @SiO 2 -Rho-Zn 2+ from the solution.
研究领域:
分析化学
·
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Nian Li,Zi-jian He,Jia-hui Zhao,Zhi-dong Zhao,Xing-rui Qi,Hao-dong Wang,Bo Liu,Hua-jie Lai,Tao Jin
Developing magnetic adsorbent that combines the merits of quick response, excellent enrichment capacity, uniform and stable dispersivity is of paramount importance in pollutants pretreatment. In this work, tunable strawberry-like Fe 3 O 4 @SiO 2 -NH 2 @Au@ 2-ME magnetic solid phase extraction materials were prepared via assembly method. The obtained nanocomposites were characterized using scanning electron microscopy, X-ray diffraction spectroscopy, infrared spectroscopy , X-ray photoelectron spectroscopy, and whereafter the preparation method was optimized. Integrating magnetic solid-phase extraction with high-performance liquid chromatography and fluorescence detection , a comprehensive enrichment and detection method toward bisphenol A (BPA) was well established. This method demonstrated high efficiency and rapidity, achieving rapid enrichment of BPA. The as-developed method exhibited good linear correlation within the range of 10.0–500 μg·L −1 , with a recovery of 85–92%. It showed excellent sensitivity and reproducibility in BPA extraction with low limit of detection (LOD, 0.274 μg·L −1 ), limit of quantitation (LOQ, 0.913 μg·L −1 ) and relative standard deviation (RSD, 1.5%, n = 6), respectively. The proposed Fe 3 O 4 @SiO 2 -NH 2 @Au nanoplatform firmly supports the envision that proper surface functionalization of magnetic substrate could promote the enrichment capacity toward various pollutants in actual application scenarios.
研究领域:
环境科学
·
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2016
·
IF 8.328
Jing Hu,Haiqiang Wang,Fan Dong,Zhongbiao Wu
Photothermal effect was for the first time utilized to capture the energy from infrared light and to promote the photocatalytic oxidation activity of NO by a simply mechanical mixing of traditional photocatalysts and core-shell structured Fe 3 O 4 @SiO 2 . Fe 3 O 4 @SiO 2 absorbed the infrared light, transferred it into thermal energy based on photothermal effect, which then accelerated the NO photocatalytic activity of traditional photocatalysts. This promotion effect led by the addition of Fe 3 O 4 @SiO 2 was confirmed by several classical photocatalysts such as TiO 2 , g-C 3 N 4 , BiOI and CeO 2 . To quantitatively characterize the photothermal effect, thermo images were taken with a thermo imager to obtain the average temperature rise of samples under the illumination of simulated solar light. Specially, P25/Fe 3 O 4 @SiO 2 was studied in depth for illustration of the promotion mechanism. Experimental results showed that with the contribution of SiO 2 shell, the photocorrosion of Fe 3 O 4 didn’t occur during photocatalytic oxidation process and the photothermal effect of Fe 3 O 4 was maintained. The quantity of Fe 3 O 4 @SiO 2 was a vital factor for promotion of photocatalytic activity and the optimum mass ratio of P25 and Fe 3 O 4 @SiO 2 was 3–1. After 120 min of illumination, the temperature of optimum P25/Fe 3 O 4 @SiO 2 rose to 57.4 °C from 25 °C and its NO conversion capability showed an enhancement of 38.9% with the comparison to pure P25. The experimental results confirmed that the rise of temperature was attributed to the photothermal effect and its contribution was the same as the directly heating of photocatalysts. Furthermore, the enhancement of NO conversion capability around 30–40% was observed for the Fe 3 O 4 @SiO 2 mixed anatase TiO 2 , g-C 3 N 4 , ZnO, BiOI and CeO 2 . In sum, we developed a new strategy for utilization of NIR light of solar energy to facilitate the photocatalytic reactions.
研究领域:
环境科学
·
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 97
·94976-94988
·
IF 3.289
Longfei Liao,Ying Liu,Zengyong Li,Junping Zhuang,Yanbin Zhou,Size Chen
Amino modified Fe3O4@SiO2 (Fe3O4@SiO2–NH2) was used to immobilize Cu2+ and VO2+ for preparing Fe3O4@SiO2–NH2–Cu2+ and Fe3O4@SiO2–NH2–VO2+ catalysts. Various technologies had been used for the characteristics of catalysts, such as XRD, XPS, FT-IR, SEM, TEM and VSM. The catalytic performance of Fe3O4@SiO2–NH2–VO2+ in HMF oxidation could be significantly enhanced by the use of Fe3O4@SiO2–NH2–Cu2+ as the co-catalysts. The type of reaction solvents showed a great influence on the oxidation of HMF. The highest HMF conversion reached up to 98.7% at 110 °C in toluene with an optimal 2,5-diformylfuran yield of 85.5%. Moreover, the Fe3O4@SiO2–NH2–Cu2+ and Fe3O4@SiO2–NH2–VO2+ catalyst exhibited great stability and could be readily applied in the next recycle after magnetic separation.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2018
·
IF 0
Wuzhu Sun,Weiyi Yang,Zhengchao Xu,Qi Li
A novel and environmentally benign approach was developed to create a Fe3O4@SiO2 core–shell structure supported Pd catalyst consisting of a superparamagnetic Fe3O4 nanosphere core, a SiO2 shell with a rough surface, Pd nanoparticles deposited on a SiO2 shell, and a cross-linked polyvinylpyrrolidone (PVP) layer. It was found that both adsorbed PVP and SiO2 shell with a rough surface from the surface-protected etching process were critical to obtain the uniform PdO deposition, while the cross-linked PVP layer could effectively anchor and protect active Pd nanoparticles to enhance their stability to resist detachment from the catalyst support and improve the reusability of the catalyst. Because of its superparamagnetic behavior, it could disperse well in aqueous solution without external magnetic field and be separated easily from aqueous solution when an external magnetic field was present. It demonstrated a high catalytic activity, desirable N2 product selectivity over 99.7%, and good reusability for the catalytic nitrite reduction in aqueous solution.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2016
·Vol. 16
·期 2
·1871-1882
·
IF 1.338
Shi Haowei,Yang Junya,Zhu Lizhong,Yang Yuxiang,Yuan Hongming,Yang Yubing,Liu Xiangnong
In this paper, the chain-like core–shell structure Fe3O4@SiO2@Chitosan composite nanoparticles were synthesized by a two-step coating and following crosslinking glutaraldehyde on chitosan shell. The composite particles showed nearly monodisperse
105 sized particles with a core diameter of 80 nm and chitosan shell thickness of 12 nm. The synthesis conditions of the product were studied, and the morphology and properties of the composite nanoparticles were characterized by IR, XRD, TEM, SEM, EDS and VSM. The adsorption properties of
Hg2+, Pb2+ or Cu2+ ions on Fe3O4, Fe3 O4@SiO2 and the composite particles were in detail studied using the colorimetric method based on forming colored mercuric dithizone, rhodamine-Pb2+ complex and DDTC-Cu(2+)
complex. The results showed, adsorption isotherm, kinetics and separation coefficient of heavy metal ions on these three magnetic nanoparticles were concerned with pH, metal ions’ electronic configuration, silica coating and chitosan shell respectively. In addition, the recycle efficiency
was also studied. The findings demonstrated that Fe3O4@SiO2@Chitosan composite nanoparticles have great application value in the adsorption and separation of heavy metal ions.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
Molecular Catalysis
·
2017
·
IF 0
Li Wang,Lei Sun,Zebin Yu,Yanping Hou,Zhenbo Peng,Fei Yang,Ying Chen,Jun Huang
The Fe 3 O 4 @SiO 2 -BiOBr (FSB) magnetic composite was prepared and introduced into the dielectric barrier discharge (DBD) system as a heterogeneous Fenton-like photocatalyst for synergistic degradation of perfluorooctanoic acid (PFOA). The FSB was characterized by X-ray diffraction, UV–vis diffuse reflectance spectra, energy dispersive X-ray spectroscopy and scanning electron microscope. Characterization results demonstrated that BiOBr was successfully coated on Fe 3 O 4 @SiO 2 , forming FSB, and it exhibited good UV & visible response. The presence of FSB accelerated PFOA degradation: PFOA removal efficiency and total organic carbon removal from DBD-FSB system increased from 73.5% to 92.9% and 28.9% to 62.5%, respectively, within 60 min under reaction conditions of 20 mg L −1 PFOA, initial pH 4.28, 100 mg L −1 FSB and 22 kV peak voltage, as compared with DBD system. Accordingly, defluorination efficiency of PFOA and energy efficiency increased from 21% to 32.8% and 46.39 mg kW −1 h −1 to 72.47 mg kW −1 h −1 , respectively. The synergetic mechanism was attributed to the combination of active species such as OH, H 2 O 2 , O 3 , directly generated from the DBD plasma and a great amount of OH generated from Fenton-like reaction initiated by FSB photocatalyst under light irradiation emitted during discharge. The OH and photogenerated holes played essential roles in the mineralization process. Based on the identified intermediates, possible degradation pathways of PFOA in DBD-FSB system were proposed, and PFOA degradation mainly occurred via the pathway of perfluoroalkyl radical pathway.
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
SENSORS AND ACTUATORS B-CHEMICAL
·
2013
·
IF 3.535
Xin Tian,Zhengping Dong,Rou Wang,Jiantai Ma
A highly selective and sensitive method for recognition of Zn 2+ and hydrogen sulfide (H 2 S) in aqueous solution has been developed by using a quinoline fluorescent sensor functionalized magnetic silica nanoparticles ( R1 ). The chemosensor R1 shows excellent fluorescence sensitivity and selectivity toward Zn 2+ and H 2 S in aqueous media , and displays off–on–off type fluorescence change with alternately adding Zn 2+ and H 2 S to the media along with reversible association–dissociation of the complex. Furthermore, the magnetic nanocomposites can be easily separated from solutions by adding an external magnetic field . Finally, using Zn 2+ and H 2 S as inputs and the fluorescence intensity as output, an INHIBIT logic gate can be constructed at the nanoscale level.
研究领域:
分析化学
·
纳米技术
·
生物医学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2021
·
IF 4.821
Yu Tian,Zhigang Xu,Yuming Yang,Dan Wang,Zhimin Liu,Xiaoxi Si
In this study, a magnetic composite material was developed by bonding the modified natural polysaccharide chitosan (CTS) with SiO 2 on the surface of magnetic Fe 3 O 4 nanoparticles to detect polychlorinated biphenyls (PCBs). The structural, porosity, and magnetic properties of Fe 3 O 4 @SiO 2 @CTS were characterized by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, nitrogen sorption, and vibrating sample magnetometry. Various experimental parameters affecting the extraction capacity were investigated, including extraction time, desorption time, desorption solvent, solution pH value, and salt ion concentration. Results showed that Fe 3 O 4 @SiO 2 @CTS exhibited excellent selectivity, easy separation by magnet, and reusability (at least 10 cycles). Under optimized experimental condition, this magnetic solid phase extraction material was applied to detect three PCBs with low limits of detection of 0.02–0.15 μg·L −1 . The linear correlation coefficient was higher than 0.998, while the recoveries ranged between 90.34% and 106.99% with the relative standard deviation less than 11.31%. The practical application of Fe 3 O 4 @SiO 2 @CTS was verified through quantitative analysis of PCB residues in environmental water, supporting its promising role in simple, convenient, and low-cost detection of PCBs in real environmental samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 47
·期 2
·828-837
·
IF 3.925
Tiantian Wan,Zulei Zhang,Hailong Wang,Yiwen Yang,Hanxing Yang,Jian Zhang,Yanbo Zeng,Lei Li,Jinchun Li
Chlorogenic acid (CGA), a cis-diol-containing compound, exhibits anti-inflammatory, antiviral, antimicrobial and anti-oxidation properties. Thus, selective determination of CGA in food products is extremely necessary. In this study, a boron affinity magnetic polymer named Fe3O4@SiO2@PIL was synthesized to detect the concentration of CGA in actual fruit samples. The Fe3O4@SiO2@PIL was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and thermogravimetric (TG) analysis. The results showed that the Fe3O4@SiO2@PIL has uniform morphology, good magnetic properties, suitable structure and high stability. The experimental assays showed that the Fe3O4@SiO2@PIL can detect the concentration of CGA within 7 min, and has a good linear relationship with CGA in the concentration range of 0.025–2 μM (R2 = 0.9989) with a detection limit of 10 nM (S/N = 3). Moreover, the Fe3O4@SiO2@PIL exhibited excellent selectivity and can be reused for at least 5 runs, indicating its good stability and reusability. Finally, the Fe3O4@SiO2@PIL was used to selectively separate CGA in real fruit samples with the recovery ranging from 93.4% to 103.0% and the relative standard deviation (RSD) between 0.7% and 5.1%. This study gives a new insight into the utilization of magnetic materials by grafting boric acid functionalized ionic liquids for specific and rapid detection of natural cis-diol-containing compounds.
研究领域:
分析化学
·
食品科学
✓ 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）