scholarly journals A Facile Preparation and Energetic Characteristics of the Core/Shell CoFe2O4/Al Nanowires Thermite Film

Micromachines ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 516
Author(s):  
Chunpei Yu ◽  
Wei Ren ◽  
Ganggang Wu ◽  
Wenchao Zhang ◽  
Bin Hu ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Laser Ignition ◽  
Heat Output ◽  
Core Shell ◽  
Optimal Thickness ◽  
Maximum Heat ◽  
The Core ◽  
Potential Applications ◽  
Facile Preparation ◽  
First Time

In this study, CoFe2O4 is selected for the first time to synthesize CoFe2O4/Al nanothermite films via an integration of nano-Al with CoFe2O4 nanowires (NWs), which can be prepared through a facile hydrothermal-annealing route. The resulting nanothermite film demonstrates a homogeneous structure and an intense contact between the Al and CoFe2O4 NWs at the nanoscale. In addition, both thermal analysis and laser ignition test reveal the superb energetic performances of the prepared CoFe2O4/Al NWs nanothermite film. Within different thicknesses of nano-Al for the CoFe2O4/Al NWs nanothermite films investigated here, the maximum heat output has reached as great as 2100 J·g−1 at the optimal thickness of 400 nm for deposited Al. Moreover, the fabrication strategy for CoFe2O4/Al NWs is also easy and suitable for diverse thermite systems based upon other composite metal oxides, such as MnCo2O4 and NiCo2O4. Importantly, this method has the featured advantages of simple operation and compatibility with microsystems, both of which may further facilitate potential applications for functional energetic chips.

scholarly journals Synthesis and Luminescence Properties of Core-Shell-Shell Composites: SiO2@PMDA-Si-Tb@SiO2 and SiO2@PMDA-Si-Tb-phen@SiO2

2019 ◽  
Author(s):  
Lina Feng ◽  
Wenxian Li ◽  
Jinrong Bao ◽  
Yushang Zheng ◽  
Yilian Li ◽  
...  
Keyword(s):  
Organic Ligand ◽  
Silica Shell ◽  
Core Shell ◽  
Organic Complex ◽  
Chemical Route ◽  
The Core ◽  
Good Solubility ◽  
Potential Applications ◽  
Long Lifetime ◽  
Terbium Ion

Two novel core-shell composites SiO2@PMDA-Si-Tb, SiO2@PMDA-Si-Tb-phen with SiO2 as the core and terbium organic complex as the shell, were successfully synthesized. The terbium ion was coordinated with organic ligand forming terbium organic complex in the shell layer. The bi-functional organosilane ((HOOC)2C6H2(CONH(CH2)3Si(OCH2CH3)3)2 (abbreviated as PMDA-Si) was used as the first ligand and phen as the second ligand. Furthermore, the silica-modified SiO2@PMDA-Si-Tb@SiO2, SiO2@PMDA-Si-Tb-phen@SiO2 core-shell-shell composites were also synthesized by sol–gel chemical route. An amorphous silica shell was coated around the SiO2@PMDA-Si-Tb and SiO2@PMDA-Si-Tb-phen core-shell composites. The core-shell and core-shell-shell composites both exhibited excellent luminescence in solid state. The luminescence of core-shell-shell composites was stronger than that of core-shell composites. Meanwhile, an improved luminescence stability property for the core-shell-shell composites was found in the aqueous solution. The core-shell-shell composites exhibited bright luminescence, high stability, long lifetime, and good solubility, which may present potential applications in the field of bio-medical.

scholarly journals Unravelling the interfacial interaction in mesoporous SiO2@nickel phyllosilicate/TiO2 core–shell nanostructures for photocatalytic activity

2020 ◽  
Vol 11 ◽  
pp. 1834-1846
Author(s):  
Bridget K Mutuma ◽  
Xiluva Mathebula ◽  
Isaac Nongwe ◽  
Bonakele P Mtolo ◽  
Boitumelo J Matsoso ◽  
...  
Keyword(s):  
Methyl Violet ◽  
Optoelectronic Properties ◽  
Shell Morphology ◽  
Bandgap Energy ◽  
Core Shell ◽  
The Core ◽  
Shell Nanostructures ◽  
Carrier Separation ◽  
First Time

Core–shell based nanostructures are attractive candidates for photocatalysis owing to their tunable physicochemical properties, their interfacial contact effects, and their efficacy in charge-carrier separation. This study reports, for the first time, on the synthesis of mesoporous silica@nickel phyllosilicate/titania (mSiO2@NiPS/TiO2) core–shell nanostructures. The TEM results showed that the mSiO2@NiPS composite has a core–shell nanostructure with a unique flake-like shell morphology. XPS analysis revealed the successful formation of 1:1 nickel phyllosilicate on the SiO2 surface. The addition of TiO2 to the mSiO2@NiPS yielded the mSiO2@NiPS/TiO2 composite. The bandgap energy of mSiO2@NiPS and of mSiO2@NiPS/TiO2 were estimated to be 2.05 and 2.68 eV, respectively, indicating the role of titania in tuning the optoelectronic properties of the SiO2@nickel phyllosilicate. As a proof of concept, the core–shell nanostructures were used as photocatalysts for the degradation of methyl violet dye and the degradation efficiencies were found to be 72% and 99% for the mSiO2@NiPS and the mSiO2@NiPS/TiO2 nanostructures, respectively. Furthermore, a recyclability test revealed good stability and recyclability of the mSiO2@NiPS/TiO2 photocatalyst with a degradation efficacy of 93% after three cycles. The porous flake-like morphology of the nickel phyllosilicate acted as a suitable support for the TiO2 nanoparticles. Further, a coating of TiO2 on the mSiO2@NiPS surface greatly affected the surface features and optoelectronic properties of the core–shell nanostructure and yielded superior photocatalytic properties.

scholarly journals Synthesis and Luminescence Properties of Core-Shell-Shell Composites: SiO2@PMDA-Si-Tb@SiO2 and SiO2@PMDA-Si-Tb-phen@SiO2

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 189 ◽  
Author(s):  
Lina Feng ◽  
Wenxian Li ◽  
Jinrong Bao ◽  
Yushan Zheng ◽  
Yilian Li ◽  
...  
Keyword(s):  
Sol Gel ◽  
Organic Ligand ◽  
Core Shell ◽  
Organic Complex ◽  
Chemical Route ◽  
The Core ◽  
Good Solubility ◽  
Potential Applications ◽  
Long Lifetime ◽  
Terbium Ion

Two novel core-shell composites SiO2@PMDA-Si-Tb, SiO2@PMDA-Si-Tb-phen with SiO2 as the core and terbium organic complex as the shell, were successfully synthesized. The terbium ion was coordinated with organic ligand forming terbium organic complex in the shell layer. The bi-functional organosilane ((HOOC)2C6H2(CONH(CH2)3Si(OCH2CH3)3)2 (abbreviated as PMDA-Si) was used as the first ligand and phen as the second ligand. Furthermore, the silica-modified SiO2@PMDA-Si-Tb@SiO2 and SiO2@PMDA-Si-Tb-phen@SiO2 core-shell-shell composites were also synthesized by sol-gel chemical route. An amorphous silica shell was coated around the SiO2@PMDA-Si-Tb and SiO2@PMDA-Si-Tb-phen core-shell composites. The core-shell and core-shell-shell composites both exhibited excellent luminescence in solid state. The luminescence of core-shell-shell composites was stronger than that of core-shell composites. Meanwhile, an improved luminescence stability property for the core-shell-shell composites was found in the aqueous solution. The core-shell-shell composites exhibited bright luminescence, high stability, long lifetime, and good solubility, which may present potential applications in the bio-medical field.

Facile preparation and enhanced microwave absorption properties of core–shell composite spheres composited of Ni cores and TiO2 shells

2015 ◽  
Vol 17 (14) ◽  
pp. 8802-8810 ◽  
Author(s):  
Biao Zhao ◽  
Gang Shao ◽  
Bingbing Fan ◽  
Wanyu Zhao ◽  
Yajun Xie ◽  
...  
Keyword(s):  
Microwave Absorption ◽  
Core Shell ◽  
Absorption Properties ◽  
Microwave Absorption Properties ◽  
The Core ◽  
Facile Preparation ◽  
Shell Composite

The microwave absorption properties of the core–shell Ni@rutile TiO2 composite are superior to those of the Ni@anatase TiO2 composite.

scholarly journals Multifunctional Silver Nanoparticles: Synthesis and Applications

2021 ◽  
Author(s):  
Nguyen Hoang Nam
Keyword(s):  
Silver Nanoparticles ◽  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Iron Oxide Nanoparticles ◽  
Silica Matrix ◽  
Oxide Nanoparticles ◽  
Core Shell ◽  
The Core ◽  
Methods Of Synthesis ◽  
Potential Applications

Multifunctional silver nanoparticles have attracted widely due to their potential applications. Based on the properties of individual silver nanoparticles, such as plasmonic and antibacterial properties, silver nanoparticles can become multifunctional by surface modifications with various surfactants or they can be combined in core-shell and composite structures with the magnetic nanoparticles to form bifunctional nanoparticles. After reviewing the methods of synthesis and applications of silver nanoparticles, the chapter describes the synthesis and the properties of the new types of multifunctional silver nanomaterials based on the plasmonic behaviors of silver nanoparticles and the iron oxide Fe3O4 superparamagnetic nanoparticles. One type is a simple combination of silver nanoparticles and iron oxide nanoparticles in a silica matrix Fe3O4/Ag-4ATP@SiO2. Other types are the core-shell structured nanoparticles, where Fe3O4 nanoparticles play as the core and silver nanoparticles are the outer shell, so-called Fe3O4@SiO2-Ag and Fe3O4-Ag. In the Fe3O4@SiO2-Ag, silver nanoparticles are reduced on the surface of silica-coated magnetic core, while in Fe3O4-Ag, silver nanoparticles are directly reduced on the amino groups functionalized on the surface of magnetic nanoparticles without coating with silica. Both of types of the multifunctional silver nanoparticles show the plasmonic and magnetic properties similar as the individual silver and iron oxide nanoparticles. Finally, some applications of those multifunctional silver nanoparticles will be discussed.

scholarly journals Preparation, characterization and luminescence properties of core–shell ternary terbium composites SiO 2(600) @Tb(MABA-Si)•L

2018 ◽  
Vol 5 (3) ◽  
pp. 171655 ◽  
Author(s):  
Yang-Yang Ma ◽  
Wen-Xian Li ◽  
Yu-Shan Zheng ◽  
Jin-Rong Bao ◽  
Yi-Lian Li ◽  
...  
Keyword(s):  
Shell Structure ◽  
Luminescence Decay ◽  
Luminescence Properties ◽  
Core Shell ◽  
Element Analysis ◽  
Strong Emission ◽  
The Core ◽  
Potential Applications ◽  
Core Shell Structure ◽  
Terbium Complexes

Two novel core–shell structure ternary terbium composites SiO 2(600) @Tb(MABA-Si)·L(L:dipy/phen) nanometre luminescence materials were prepared by ternary terbium complexes Tb(MABA-Si)·L 2 ·(ClO 4 ) 3 ·2H 2 O shell grafted onto the surface of SiO 2 microspheres. And corresponding ternary terbium complexes were synthesized using (CONH(CH 2 ) 3 Si(OCH 2 CH 3 ) 3 ) 2 (denoted as MABA-Si) as first ligand and L as second ligand coordinated with terbium perchlorate. The as-synthesized products were characterized by means of IR spectra, 1 HNMR, element analysis, molar conductivity, SEM and TEM. It was found that the first ligand MABA-Si of terbium ternary complex hydrolysed to generate the Si–OH and the Si–OH condensate with the Si–OH on the surface of SiO 2 microspheres; then ligand MABA-Si grafted onto the surface of SiO 2 microspheres. The diameter of SiO 2 core of SiO 2(600) @Tb(MABA-Si)·L was approximately 600 nm. Interestingly, the luminescence properties demonstrate that the two core–shell structure ternary terbium composites SiO 2(600) Tb(MABA-Si)·L(dipy/phen) exhibit strong emission intensities, which are 2.49 and 3.35 times higher than that of the corresponding complexes Tb(MABA-Si)·L 2 ·(ClO 4 ) 3 ·2H 2 O, respectively. Luminescence decay curves show that core–shell structure ternary terbium composites have longer lifetime. Excellent luminescence properties enable the core–shell materials to have potential applications in medicine, industry, luminescent fibres and various biomaterials fields.

Core/Shell Nanostructured Materials for Sustainable Processes

2016 ◽  
Vol 14 (3) ◽  
pp. 667-684 ◽  
Author(s):  
Zhenkun Sun ◽  
Serge Kaliaguine
Keyword(s):  
Nanostructured Materials ◽  
Shell Structure ◽  
Materials Design ◽  
Simple Solution ◽  
Core Shell ◽  
Design Problems ◽  
Structured Materials ◽  
The Core ◽  
Potential Applications ◽  
Core Shell Structure

Abstract In this paper, we summarize recent research efforts from our laboratory concerning the application of core/shell structured materials for sustainability. Special attention is paid to the synthesis of different core/shell materials from nanoscale to microscale by various methods. The potential applications of our prepared novel materials with core/shell configuration are discussed, which illustrates the diversity of situations where the core/shell structure brings a simple solution to different materials design problems.

scholarly journals Imparting multi-functionality to covalent organic framework nanoparticles by the dual-ligand assistant encapsulation strategy

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Liang Chen ◽  
Wenxing Wang ◽  
Jia Tian ◽  
Fanxing Bu ◽  
Tiancong Zhao ◽  
...  
Keyword(s):  
Near Infrared ◽  
Core Shell ◽  
Tissue Penetration ◽  
Deep Tissue ◽  
Functional Nanoparticles ◽  
The Core ◽  
Shell Nanostructures ◽  
Potential Applications ◽  
Interfacial Growth ◽  
Promising Type

AbstractThe potential applications of covalent organic frameworks (COFs) can be further developed by encapsulating functional nanoparticles within the frameworks. However, the synthesis of monodispersed core@shell structured COF nanocomposites without agglomeration remains a significant challenge. Herein, we present a versatile dual-ligand assistant strategy for interfacial growth of COFs on the functional nanoparticles with abundant physicochemical properties. Regardless of the composition, geometry or surface properties of the core, the obtained core@shell structured nanocomposites with controllable shell-thickness are very uniform without agglomeration. The derived bowl-shape, yolk@shell, core@satellites@shell nanostructures can also be fabricated delicately. As a promising type of photosensitizer for photodynamic therapy (PDT), the porphyrin-based COFs were grown onto upconversion nanoparticles (UCNPs). With the assistance of the near-infrared (NIR) to visible optical property of UCNPs core and the intrinsic porosity of COF shell, the core@shell nanocomposites can be applied as a nanoplatform for NIR-activated PDT with deep tissue penetration and chemotherapeutic drug delivery.

Magnetic Properties of Fe3O4/CoFe2O4 Composite Nanoparticles with Core/Shell Architecture

2020 ◽  
Vol 65 (10) ◽  
pp. 904
Author(s):  
V. O. Zamorskyi ◽  
Ya. M. Lytvynenko ◽  
A. M. Pogorily ◽  
A. I. Tovstolytkin ◽  
S. O. Solopan ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Spinel Ferrite ◽  
Composite Nanoparticles ◽  
Core Shell ◽  
Cofe2o4 Nanoparticles ◽  
Core Diameter ◽  
The Core ◽  
Shell Particles ◽  
Interface Parameters ◽  
Shell Composite

Magnetic properties of the sets of Fe3O4(core)/CoFe2O4(shell) composite nanoparticles with a core diameter of about 6.3 nm and various shell thicknesses (0, 1.0, and 2.5 nm), as well as the mixtures of Fe3O4 and CoFe2O4 nanoparticles taken in the ratios corresponding to the core/shell material contents in the former case, have been studied. The results of magnetic research showed that the coating of magnetic nanoparticles with a shell gives rise to the appearance of two simultaneous effects: the modification of the core/shell interface parameters and the parameter change in both the nanoparticle’s core and shell themselves. As a result, the core/shell particles acquire new characteristics that are inherent neither to Fe3O4 nor to CoFe2O4. The obtained results open the way to the optimization and adaptation of the parameters of the core/shell spinel-ferrite-based nanoparticles for their application in various technological and biomedical domains.

Non-Plasmonic SERS with Silicon: Is It Really Safe? New Insights into Opto-Thermics of Core/Shell Microbeads

2018 ◽  
Author(s):  
Nicolò Bontempi ◽  
Irene Vassalini ◽  
Stefano Danesi ◽  
Matteo Ferroni ◽  
Paolo Colombi ◽  
...  
Keyword(s):  
Critical Role ◽  
Raman Laser ◽  
Core Shell ◽  
Thermal Coupling ◽  
Melting Points ◽  
Experimental Proof ◽  
Weakly Coupled ◽  
Light Management ◽  
Laser Sources ◽  
First Time

<p>Here we investigate for the first time the opto-thermal behavior of SiO<sub>2</sub>/Si core/shell microbeads (Si-rex) irradiated with three common Raman laser sources (lambda=532, 633, 785 nm) under real working conditions. We obtained an experimental proof of the critical role played by bead size and aggregation in heat and light management, demonstrating that in the case of strong opto-thermal coupling the temperature can exceed that of the melting points of both core and shell components. In addition, we also show that weakly coupled beads can be utilized as stable substrates for plasmon-free SERS experiments.</p>

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