Modeling spectral properties of transparent matrix composites  containing core-shell nanoparticles

Optical properties of transparent matrix composites containing metal nanoparticles coated with an oxide shell were numerically simulated based on the Aden-Kerker theory applicable for concentric spheres. Using pentaerythritol tetranitrate composites (containing Al/Al2O3 nanoparticles) as an example, the linear scattering and absorption coefficients as well as the total reflectance and transmittance and collimated beam transmittance were shown to be determined by the sample thickness, the nanoparticle radius, the mass fraction of nanoparticles, and mass fraction of the oxide in the nanoparticles. An approach to determining the said parameters based on the comparison of the calculated spectral dependencies of the reflectance and transmittance with the experimental ones was suggested. The nanoparticle radius was determined with the minimum error (of about 2 – 3 %), while the nanoparticle mass fraction and oxide mass fraction were weak parameters determined with a 25 % error.

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Natural Polyampholyte-Based Core−Shell Nanoparticles withN-Carboxyethylchitosan-Containing Core and Poly(ethylene oxide) Shell

Biomacromolecules ◽

10.1021/bm8013186 ◽

2009 ◽

Vol 10 (4) ◽

pp. 838-844 ◽

Cited By ~ 11

Author(s):

Rosica Mincheva ◽

François Bougard ◽

Dilyana Paneva ◽

Magali Vachaudez ◽

Nevena Manolova ◽

...

Keyword(s):

Ethylene Oxide ◽

Oxide Shell ◽

Core Shell ◽

Shell Nanoparticles ◽

Poly Ethylene Oxide ◽

Poly Ethylene ◽

Core Shell Nanoparticles

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Characterization of a Porous Carbon Material Functionalized with Cobalt-Oxide/Cobalt Core-Shell Nanoparticles for Lithium Ion Battery Electrodes

MRS Advances ◽

10.1557/adv.2016.263 ◽

2016 ◽

Vol 1 (15) ◽

pp. 1061-1066

Author(s):

Dalaver H. Anjum ◽

Shahid Rasul ◽

Manuel A. Roldan-Gutierrez ◽

Pedro M. F. J. Costa

Keyword(s):

Lithium Ion Battery ◽

Cobalt Oxide ◽

Lithium Ion ◽

Oxide Shell ◽

Porous Carbon Material ◽

Core Shell ◽

Shell Nanoparticles ◽

Transmission Electron ◽

Core Shell Nanoparticles ◽

Type Lattice

ABSTRACTA nanoporous carbon (C) material, functionalized with Cobalt-Oxide/Cobalt (CoO/Co) core-shell nanoparticles (NPs), was structurally and chemically characterized with transmission electron microcopy (TEM) while its electrochemical response for Lithium ion battery (LIB) applications was evaluated as well. The results herein show that the nanoporous C material was uniformly functionalized with the CoO/Co core-shell NPs. Further the NPs were crystalline with fcc-type lattice on the Co2+ oxide shell and hcp-type core of metallic Co0. The electrochemical study was carried out by using galvanostatic charge/discharge cycling at a current density of 1000 mA g−1. The potential of this hybrid material for LIB applications was confirmed and it is attributed to the successful dispersion of the Co2+/ Co0 NPs in the C support.

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Lab and Pilot-Scale Synthesis of MxOm@SiC Core–Shell Nanoparticles

Materials ◽

10.3390/ma13030649 ◽

2020 ◽

Vol 13 (3) ◽

pp. 649 ◽

Cited By ~ 1

Author(s):

Àngela Ribes ◽

Santiago Sánchez-Cabezas ◽

Andy Hernández-Montoto ◽

Luis A. Villaescusa ◽

Elena Aznar ◽

...

Keyword(s):

Metal Matrix Composites ◽

Metal Matrix ◽

Scale Up ◽

Pilot Scale ◽

Core Shell ◽

Matrix Composites ◽

Shell Nanoparticles ◽

X Ray ◽

Scanning Transmission ◽

Core Shell Nanoparticles

The addition of light ceramic particles to bulk technological materials as reinforcement to improve their mechanical properties has attracted increasing interest in the last years. The metal matrix composites obtained using nanoparticles have been reported to exhibit an improvement of their properties due to the decrease in the size of the ceramic additives to the nanoscale. Additionally, important effects such as the dispersion of the nanoparticles, wettability, and low reactivity can be controlled by the modification of the nanoparticles’ surface. In this work, we present the preparation of core–shell MxOm@SiC nanoparticles with different shell compositions. The accurate and reproducible preparation is developed both at the lab and pilot scale. The synthesis of these core–shell nanoparticles and their scale-up production are fundamental steps for their industrial use as additives in metal matrix composites and alloys. Powder X-ray diffraction and energy dispersive X-ray (EDX) coupled with scanning transmission electron microscopy (STEM) are used to corroborate the formation of the core–shell systems, whereas line scan-EDX analysis allows measuring the average shell thickness.

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Correlated Transitions of Pb/PbO Core-Shell Nanoparticles Induced by Electron Beam Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.643.199 ◽

2013 ◽

Vol 643 ◽

pp. 199-202

Author(s):

Yang Zhou ◽

Long Bing He ◽

Min Han ◽

Bo Xie

Keyword(s):

Electron Beam ◽

Moderate Intensity ◽

Oxide Shell ◽

Core Shell ◽

Inelastic Electron ◽

Shell Nanoparticles ◽

Electron Collisions ◽

Intense Electron Beam ◽

Amorphous Particles ◽

Core Shell Nanoparticles

Nanoscale thermodynamics and kinetics were explored via the manipulation of Pb/PbO core-shell nanoparticles with a focused electron beam which served as a nanometer heating probe. In the electron transmission microscope (TEM), when an electron beam of moderate intensity was used to irradiate the nanoparticles, the amorphous particles gradually crystallized and showed distinct boundaries between lead cores and oxide shells. In such a way, the oxide shell could be easily measured to be 0.5-2 nanometers. With a high intensity electron beam, melting of the lead cores could be observed, indicating a sufficient local temperature increasing induced by the concentrated heat generated by inelastic electron collisions. The fluidic metal core erupted out through the cracked shells accompanied with the vanish of the boundaries between the cores and shells. Manipulations on nanoparticle decorated carbon wires proved that the lead oxide shells could sustain the irradiation of intense electron beam.

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Iron Oxide Composite Nanoparticles and Sensing Properties

MRS Proceedings ◽

10.1557/proc-0900-o06-26 ◽

2005 ◽

Vol 900 ◽

Author(s):

Lingyan Wang ◽

Xiajing Shi ◽

Sakienah Mahs ◽

Jeongku Choi ◽

Karan Sarup ◽

...

Keyword(s):

Iron Oxide ◽

Oxide Shell ◽

Core Shell ◽

Shell Nanoparticles ◽

Fe Oxide ◽

Sensing Properties ◽

Volatile Organic ◽

Unique Aspect ◽

Core Shell Nanoparticles ◽

Piezoelectric Devices

ABSTRACTThis paper reports findings of an investigation of the synthesis of monolayer-capped iron oxide and core (iron oxide)-shell (gold) nanocomposite and their assembly towards thin films as sensing materials. Pre-synthesized and size-defined iron oxide nanoparticles were used as seeding materials for the reduction of gold precursors, which was shown to be effective for coating the iron oxide cores with gold shells (Fe oxide@Au). The unique aspect of our synthesis is the formation of Fe oxide@Au core-shell nanoparticles with controllable surface properties. By controlling the reaction temperatures and manipulating the capping agent properties and solution compositions, the size, shape, composition, and monodispersity can be tailored. The core-shell nanoparticles were shown to form molecularly-mediated thin film assemblies using molecular mediators. The sensing properties of the nanostructures on piezoelectric devices were examined for the detection of volatile organic compounds. The preliminary results have provided important insights into the design of core-shell nanocomposites as sensing materials.

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Influence of Shell Parameters on Optical Properties of Spherical Metallic Core-Oxide Shell Nanoparticles

Journal of Nanomaterials ◽

10.1155/2015/812617 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Victor K. Pustovalov ◽

Liudmila G. Astafyeva

Keyword(s):

Metallic Nanoparticles ◽

Oxide Shell ◽

Spectral Interval ◽

Metal Core ◽

Metal Shell ◽

Shell Nanoparticles ◽

Wide Range ◽

Potential Applications ◽

Efficiency Factors ◽

Core Shell Nanoparticles

Different metal homogeneous nanoparticles have been extensively studied in recent years due to their wide range of potential applications. It is very interesting to investigate core-shell nanoparticles with oxide shell from core metal. The formation of oxide shell on metallic nanoparticles can be achieved by different chemical and physical methods including also natural oxidation of pure metallic nanoparticles in gaseous or liquid media, containing oxygen components (air, water, etc.). We numerically calculated efficiency factors of absorptionKabs, scatteringKsca, and extinctionKextof radiation with wavelengthλin the spectral interval 150–1000 nm by spherical homogeneous metallic and two-layered (metal core – oxide metal shell) nanoparticles: Al, Al-Al2O3and Zn, Zn-ZnO with core radii in the range 5–50 nm and shell thickness 5 nm. Analysis of presented results has been carried out.

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Adsorption of HCN onto Copper@Copper-Oxide Core–Shell Nanoparticle Systems

Adsorption Science & Technology ◽

10.1260/026361709790252632 ◽

2009 ◽

Vol 27 (4) ◽

pp. 349-361

Author(s):

Septimus H. Liang ◽

Shiliang Wang ◽

David B. Pedersen

Keyword(s):

Reaction Mechanism ◽

Copper Oxide ◽

Oxide Shell ◽

Core Shell ◽

Copper Nanoparticle ◽

Filter Media ◽

Shell Nanoparticles ◽

Copper Compounds ◽

Core Shell Nanoparticles ◽

Carbon Based

Copper compounds are widely used as impregnants that enhance the removal of HCN by carbon-based filter media. The reaction mechanism involved is poorly understood. In this study, we have followed the reaction of HCN with pristine copper, copper oxide (CuO and Cu2O) and copper@copperoxide (Cu@Cu2O) core–shell nanoparticles of well-defined size and composition. We have established a cooperative reaction mechanism where both the copper oxide shell and copper core are required for the chemisorption of HCN onto copper nanoparticle impregnants. The suitability of copper@copperoxide nanoparticles as impregnants for the removal of HCN in respirator canisters is discussed.

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On the synthesis of bi-magnetic manganese ferrite-based core–shell nanoparticles

Nanoscale Advances ◽

10.1039/d0na00967a ◽

2021 ◽

Author(s):

Marco Sanna Angotzi ◽

Valentina Mameli ◽

Claudio Cara ◽

Davide Peddis ◽

Huolin L. Xin ◽

...

Keyword(s):

Iron Oxide ◽

Cobalt Ferrite ◽

Magnetic Core ◽

Oxide Shell ◽

Core Shell ◽

Manganese Ferrite ◽

Shell Nanoparticles ◽

Seed Mediated ◽

Core Shell Nanoparticles

Dissolution phenomena in seed-mediated growth approaches of MnFe2O4-based bi-magnetic core–shell nanoheterostructures with a cobalt ferrite or spinel iron oxide shell.

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