High efficiency reductive degradation of a wide range of azo dyes by SiO 2 -Co 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.

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Synthesis and Advanced Characterization of Polymer-Protein Core-Shell Nanoparticles

Catalysts ◽

10.3390/catal11060730 ◽

2021 ◽

Vol 11 (6) ◽

pp. 730

Author(s):

Erik Sarnello ◽

Tao Li

Keyword(s):

Particle Size ◽

Small Angle ◽

Core Shell ◽

Assembly Process ◽

Shell Nanoparticles ◽

X Ray ◽

X Ray Scattering ◽

Wide Range ◽

Core Shell Nanoparticles ◽

Ray Scattering

Enzyme immobilization techniques are widely researched due to their wide range of applications. Polymer–protein core–shell nanoparticles (CSNPs) have emerged as a promising technique for enzyme/protein immobilization via a self-assembly process. Based on the desired application, different sizes and distribution of the polymer–protein CSNPs may be required. This work systematically studies the assembly process of poly(4-vinyl pyridine) and bovine serum albumin CSNPs. Average particle size was controlled by varying the concentrations of each reagent. Particle size and size distributions were monitored by dynamic light scattering, ultra-small-angle X-ray scattering, small-angle X-ray scattering and transmission electron microscopy. Results showed a wide range of CSNPs could be assembled ranging from an average radius as small as 52.3 nm, to particles above 1 µm by adjusting reagent concentrations. In situ X-ray scattering techniques monitored particle assembly as a function of time showing the initial particle growth followed by a decrease in particle size as they reach equilibrium. The results outline a general strategy that can be applied to other CSNP systems to better control particle size and distribution for various applications.

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Crystalline–Amorphous Permalloy@Iron Oxide Core–Shell Nanoparticles Decorated on Graphene as High-Efficiency, Lightweight, and Hydrophobic Microwave Absorbents

ACS Applied Materials & Interfaces ◽

10.1021/acsami.8b18875 ◽

2019 ◽

Vol 11 (6) ◽

pp. 6374-6383 ◽

Cited By ~ 35

Author(s):

Yong Sun ◽

Junwei Zhang ◽

Yan Zong ◽

Xia Deng ◽

Hongyang Zhao ◽

...

Keyword(s):

Iron Oxide ◽

High Efficiency ◽

Core Shell ◽

Shell Nanoparticles ◽

Iron Oxide Core ◽

Core Shell Nanoparticles

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Synthesis and Photocatalytic Activity of Magnetically Recoverable Core-Shell Nanoparticles

International Journal of Photoenergy ◽

10.1155/2014/867565 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Zhen Peng ◽

Hua Tang ◽

Yao Tang ◽

Ke Fu Yao ◽

Hong Hong Shao

Keyword(s):

Photocatalytic Activity ◽

High Efficiency ◽

Sol Gel ◽

High Photocatalytic Activity ◽

Core Shell ◽

Oily Wastewater ◽

Strong Response ◽

Shell Nanoparticles ◽

Oil Concentration ◽

Core Shell Nanoparticles

TiO2/SiO2/Fe3O4(TSF) core-shell nanoparticles with good photocatalytic activity that are capable of fast magnetic separation have been successfully prepared by chemical coprecipitation and two-step sol-gel process. The as-prepared TSF nanoparticles were calcined at high temperature in order to transform the amorphous titanium dioxide into a photoactive crystalline phase. The calcined nanoparticles are composed of a Fe3O4core with a strong response to external magnetic fields, a SiO2intermediary layer, and a TiO2outshell. Vibration sample magnetometer (VSM) analysis confirms the superparamagnetism of calcined nanoparticles, which can enhance the recoverable properties of the novel photocatalyst. When the TiO2/SiO2/Fe3O4core-shell nanoparticles are added to the crude oily wastewater, they exhibit high photocatalytic activity in the degradation of crude oily wastewater. The oil concentration could be reduced to lower than 30 ppm within 20 minutes for the case of initial oil concentration less than 350 ppm. It has been found that the TSF nanoparticles could be easily separated from the wastewater and withdrawn by using an external magnetic field. The recovered TSF nanoparticles possess high efficiency in the degradation of crude oily wastewater even after three times successive reuse. The present results indicate that TSF core-shell nanoparticles possess great application perspectives in the degradation of crude oily wastewater.

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Controlled Synthesis and Characterization of Co-Au Core-shell Nanoparticles

MRS Proceedings ◽

10.1557/proc-877-s3.4 ◽

2005 ◽

Vol 877 ◽

Author(s):

Yuping Bao ◽

Hector Calderon ◽

Kannan M. Krishnan

Keyword(s):

Core Shell ◽

Gold Compound ◽

Contrast Imaging ◽

Shell Nanoparticles ◽

Transmission Electron ◽

Wide Range ◽

High Resolution Tem ◽

Core Shell Nanoparticles ◽

Z Contrast ◽

First Time

AbstractCo-Au Core-shell nanoparticles are synthesized by slowly reducing an organo-gold compound on pre-made cobalt seeds with a weak reducer at mild condition. For the first time, these coreshell nanoparticles are generated in non-polar solvent in a controlled manner. The formation theory of core-shell structure, especially the seed size effect, is addressed as well. These coreshell structures are confirmed with a wide range of transmission electron microscopy (TEM) methods, which includes routine TEM images, high resolution TEM, and z-contrast imaging.

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Bubble nucleation and migration in a lead–iron hydr(oxide) core–shell nanoparticle

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1510342112 ◽

2015 ◽

Vol 112 (42) ◽

pp. 12928-12932 ◽

Cited By ~ 10

Author(s):

Kaiyang Niu ◽

Timofey Frolov ◽

Huolin L. Xin ◽

Junling Wang ◽

Mark Asta ◽

...

Keyword(s):

Iron Hydroxide ◽

Steel Corrosion ◽

Elastic Interaction ◽

Bubble Nucleation ◽

Core Shell ◽

In Situ Observation ◽

Shell Nanoparticles ◽

Wide Range ◽

And Migration ◽

Core Shell Nanoparticles

Iron hydroxide is found in a wide range of contexts ranging from biominerals to steel corrosion, and it can transform to anhydrous oxide via releasing O2 gas and H2O. However, it is not well understood how gases transport through a crystal lattice. Here, we present in situ observation of the nucleation and migration of gas bubbles in iron (hydr)oxide using transmission electron microscopy. We create Pb–FeOOH model core–shell nanoparticles in a liquid cell. Under electron irradiation, iron hydroxide transforms to iron oxide, during which bubbles are generated, and they migrate through the shell to the nanoparticle surface. Geometric phase analysis of the shell lattice shows an inhomogeneous stain field at the bubbles. Our modeling suggests that the elastic interaction between the core and the bubble provides a driving force for bubble migration.

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Facile synthesis of high-performance SiO2@Au core–shell nanoparticles with high SERS activity

RSC Advances ◽

10.1039/c8ra05213a ◽

2018 ◽

Vol 8 (54) ◽

pp. 30825-30831 ◽

Cited By ~ 4

Author(s):

Keli Wang ◽

Yanping Wang ◽

Chongwen Wang ◽

Xiaofei Jia ◽

Jia Li ◽

...

Keyword(s):

High Performance ◽

Core Shell ◽

Facile Synthesis ◽

Shell Nanoparticles ◽

Wide Range ◽

Core Shell Nanoparticles ◽

General Method

This study proposes a facile and general method for fabricating a wide range of high-performance SiO2@Au core–shell nanoparticles (NPs).

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Guanidine functionalized core–shell structured magnetic cobalt-ferrite: an efficient nanocatalyst for sonochemical synthesis of spirooxindoles in water

RSC Advances ◽

10.1039/d1ra00967b ◽

2021 ◽

Vol 11 (25) ◽

pp. 15360-15368

Author(s):

Mahla Dadaei ◽

Hossein Naeimi

Keyword(s):

Cobalt Ferrite ◽

Core Shell ◽

Shell Material ◽

Sonochemical Synthesis ◽

Shell Nanoparticles ◽

The Core ◽

Wide Range ◽

Core Shell Nanoparticles

The core/shell nanoparticles have a wide range of applications in the science of chemistry and biomedical. The core-shell material can be different and modified by changing the ingredients or the ratio of core to the shell.

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NIR-II Upconversion Photoluminescence of Er3+ Doped LiYF4 and NaY(Gd)F4 Core-Shell Nanoparticles

Frontiers in Chemistry ◽

10.3389/fchem.2021.690833 ◽

2021 ◽

Vol 9 ◽

Author(s):

Qilong Feng ◽

Wenjing Zheng ◽

Jie Pu ◽

Qiaoli Chen ◽

Wei Shao

Keyword(s):

Near Infrared ◽

High Efficiency ◽

Protective Layer ◽

Luminescent Properties ◽

Core Shell ◽

Potential Candidate ◽

Shell Nanoparticles ◽

Surface Luminescence ◽

The Difference ◽

Core Shell Nanoparticles

The availability of colloidal nano-materials with high efficiency, stability, and non-toxicity in the near infrared-II range is beneficial for biological diagnosis and therapy. Rare earth doped nanoparticles are ideal luminescent agents for bio-applications in the near infrared-II range due to the abundant energy level distribution. Among them, both excitation and emission range of Er3+ ions can be tuned into second biological window range. Herein, we report the synthesis of ∼15 nm LiYF4, NaYF4, and NaGdF4 nanoparticles doped with Er3+ ions and their core-shell structures. The luminescent properties are compared, showing that Er3+ ions with single-doped LiYF4 and NaYF4 nanoparticles generate stronger luminescence than Er3+ ions with doped NaGdF4, despite the difference in relative intensity at different regions. By epitaxial growth an inert homogeneous protective layer, the surface luminescence of the core-shell structure is further enhanced by about 5.1 times, 6.5 times, and 167.7 times for LiYF4, NaYF4, and NaGdF4, respectively. The excellent luminescence in both visible and NIR range of these core-shell nanoparticles makes them potential candidate for bio-applications.

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