Magnetic core–shell-structured nanoporous organosilica microspheres for the Suzuki–Miyaura coupling of aryl chlorides: improved catalytic activity and facile catalyst recovery

2012 ◽  
Vol 22 (14) ◽  
pp. 6639 ◽  
Author(s):  
Hengquan Yang ◽  
Guang Li ◽  
Zhancheng Ma
Keyword(s):  
Catalytic Activity ◽  
Magnetic Core ◽  
Core Shell ◽  
Catalyst Recovery ◽  
Aryl Chlorides

Preparation, Characterization and Visible-Light Catalytic Activity of Core-Shell Structure NiFe2O4@TiO2 Ferrite Nanoparticles

2016 ◽  
Vol 680 ◽  
pp. 272-277
Author(s):  
Zhou Li Lu ◽  
Peng Zhao Gao ◽  
Rui Xue Ma ◽  
Yu Kun Sun ◽  
Dong Yun Li
Keyword(s):  
Catalytic Activity ◽  
Visible Light ◽  
Shell Structure ◽  
Shell Thickness ◽  
Spinel Ferrite ◽  
Sol Gel ◽  
Magnetic Core ◽  
Core Shell ◽  
Calcination Temperatures ◽  
Core Shell Structure

The core-shell structure NiFe2O4@TiO2 nanoparticles was successfully prepared using a sol-gel method, the influence of shell thickness and calcination temperatures on the composition, microstructure, magnetic properties and visible-light catalytic activity of the nanoparticles was studied by XRD, TEM, Uv–vis, vibrating sample magnetometer, etc. Results showed the main composition of core in NiFe2O4@TiO2 was spinel ferrite, and the shell was anatase TiO2, and theshell thickness increased significantly with the increase of TiO2 content, ranging from 10nm to 50nm. The Ms and Mr of nanoparticles decreased with the increase of TiO2 content, and no obvious reaction between the magnetic core and shell occurred; visible-light degradation percent of NiFe2O4@TiO2 nanoparticles increased along with the increase of TiO2 content, whereas the recovery rate of it decreased. Degradation percent and the recovery percent of NiFe2O4@TiO2-50 still reached 93.7% and 90.5%, even after 10 cycle times, respectively, possessing the excellent long-term stability.

scholarly journals Study on Photodegradation Activity of Fe3O4@SiO2@TiO2-Ce/rGO Magnetic Photocatalyst

2021 ◽  
Author(s):  
Weiyan Cao ◽  
Liu Xijun ◽  
Wang Yuwei ◽  
Zhang Yong ◽  
Han Xianxin ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Sol Gel ◽  
Magnetic Core ◽  
Nano Composites ◽  
Core Shell ◽  
Magnetic Composite ◽  
Composite Nanomaterials ◽  
Experimental Conditions ◽  
Magnetic Photocatalyst ◽  
Composite Photocatalyst

Abstract The magnetic core-shell Fe3O4@SiO2@TiO2-Ce/rGO composite nanomaterials were prepared by sol-gel method and hydrothermal method, composite photocatalyst doped with metal and loaded with graphene, the catalytic activity has been greatly improved. Under normal experimental conditions (pH = 7, [MB] = 10mg/L, magnetic composite photocatalyst concentration = 0.1g/50mL), Fe3O4@SiO2@TiO2-Ce/rGO nano-composites photocatalyst maximum degrade MB reaches 98.2% in 140 minutes.

scholarly journals Fabrication of copper(II)-coated magnetic core-shell nanoparticles Fe3O4@SiO2-2-aminobenzohydrazide and investigation of its catalytic application in the synthesis of 1,2,3-triazole compounds

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
H. Rajabi-Moghaddam ◽  
M. R. Naimi-Jamal ◽  
M. Tajbakhsh
Keyword(s):  
High Efficiency ◽  
Click Reaction ◽  
Magnetic Core ◽  
Core Shell ◽  
Isatoic Anhydride ◽  
Shell Nanoparticles ◽  
Triazole Derivatives ◽  
Catalytic Application ◽  
Ft Ir ◽  
Core Shell Nanoparticles

AbstractIn the present work, an attempt has been made to synthesize the 1,2,3-triazole derivatives resulting from the click reaction, in a mild and green environment using the new copper(II)-coated magnetic core–shell nanoparticles Fe3O4@SiO2 modified by isatoic anhydride. The structure of the catalyst has been determined by XRD, FE-SEM, TGA, VSM, EDS, and FT-IR analyzes. The high efficiency and the ability to be recovered and reused for at least up to 6 consecutive runs are some superior properties of the catalyst.

scholarly journals Removal of Cd(II) from Micro-Polluted Water by Magnetic Core-Shell Fe3O4@Prussian Blue

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2497
Author(s):  
Xinxin Long ◽  
Huanyu Chen ◽  
Tijun Huang ◽  
Yajing Zhang ◽  
Yifeng Lu ◽  
...  
Keyword(s):  
Prussian Blue ◽  
Co Adsorption ◽  
Magnetic Core ◽  
Diameter Distribution ◽  
Polluted Water ◽  
Core Shell ◽  
Freundlich Model ◽  
Rate Limiting Step ◽  
Rate Limiting

A novel core-shell magnetic Prussian blue-coated Fe3O4 composites (Fe3O4@PB) were designed and synthesized by in-situ replication and controlled etching of iron oxide (Fe3O4) to eliminate Cd (II) from micro-polluted water. The core-shell structure was confirmed by TEM, and the composites were characterized by XRD and FTIR. The pore diameter distribution from BET measurement revealed the micropore-dominated structure of Fe3O4@PB. The effects of adsorbents dosage, pH, and co-existing ions were investigated. Batch results revealed that the Cd (II) adsorption was very fast initially and reached equilibrium after 4 h. A pH of 6 was favorable for Cd (II) adsorption on Fe3O4@PB. The adsorption rate reached 98.78% at an initial Cd (II) concentration of 100 μg/L. The adsorption kinetics indicated that the pseudo-first-order and Elovich models could best describe the Cd (II) adsorption onto Fe3O4@PB, indicating that the sorption of Cd (II) ions on the binding sites of Fe3O4@PB was the main rate-limiting step of adsorption. The adsorption isotherm well fitted the Freundlich model with a maximum capacity of 9.25 mg·g−1 of Cd (II). The adsorption of Cd (II) on the Fe3O4@PB was affected by co-existing ions, including Cu (II), Ni (II), and Zn (II), due to the competitive effect of the co-adsorption of Cd (II) with other co-existing ions.

scholarly journals Multifunktionale bakterielle Nanomagnete für Biotechnologie und Medizin

BIOspektrum ◽  
2021 ◽  
Vol 27 (4) ◽  
pp. 442-444
Author(s):  
Frank Mickoleit ◽  
Sabine Rosenfeldt ◽  
Anna S. Schenk ◽  
Dirk Schüler ◽  
René Uebe
Keyword(s):  
Particle Production ◽  
Magnetotactic Bacteria ◽  
Magnetic Core ◽  
High Yield ◽  
Core Shell ◽  
Shell Nanoparticles ◽  
Magnetospirillum Gryphiswaldense ◽  
Core Shell Nanoparticles ◽  
Genetic Toolkit ◽  
The Way

AbstractBacterial magnetosomes represent magnetic core-shell nanoparticles biomineralized by magnetotactic bacteria like Magnetospirillum gryphiswaldense. The establishment of fermentation regimes for high-yield particle production, standardized isolation procedures as well as the development of a genetic toolkit for the generation of “tailored” particles might soon pave the way for the application of engineered magnetosomes in the biomedical and biotechnological field.

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