Asymptotic analysis for the electric field concentration with geometry of the core-shell structure

<p style='text-indent:20px;'>In the perfect conductivity problem arising from composites, the electric field may become arbitrarily large as <inline-formula><tex-math id="M1">\begin{document}$ \varepsilon $\end{document}</tex-math></inline-formula>, the distance between the inclusions and the matrix boundary, tends to zero. In this paper, by making clear the singular role of the blow-up factor <inline-formula><tex-math id="M2">\begin{document}$ Q[\varphi] $\end{document}</tex-math></inline-formula> introduced in [<xref ref-type="bibr" rid="b27">27</xref>] for some special boundary data of even function type with <inline-formula><tex-math id="M3">\begin{document}$ k $\end{document}</tex-math></inline-formula>-order growth, we prove the optimality of the blow-up rate in the presence of <inline-formula><tex-math id="M4">\begin{document}$ m $\end{document}</tex-math></inline-formula>-convex inclusions close to touching the matrix boundary in all dimensions. Finally, we give closer analysis in terms of the singular behavior of the concentrated field for eccentric and concentric core-shell geometries with circular and spherical boundaries from the practical application angle.</p>

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Essential role of the interfacial interaction in the core-shell electrode for its enhanced electrochemical performance

Chemical Engineering Journal ◽

10.1016/j.cej.2021.130895 ◽

2021 ◽

pp. 130895

Author(s):

Jiawei Wang ◽

Mingshuai Sun ◽

Fumin Wang ◽

Xubin Zhang ◽

Jian Song ◽

...

Keyword(s):

Electrochemical Performance ◽

Essential Role ◽

Interfacial Interaction ◽

Core Shell ◽

The Core ◽

Enhanced Electrochemical Performance

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Unravelling the origin of the giant Zn deficiency in wurtzite type ZnO nanoparticles

Scientific Reports ◽

10.1038/srep12914 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 12

Author(s):

Adèle Renaud ◽

Laurent Cario ◽

Xavier Rocquefelte ◽

Philippe Deniard ◽

Eric Gautron ◽

...

Keyword(s):

Zno Nanoparticles ◽

Charge Carriers ◽

Zn Deficiency ◽

Core Shell ◽

Bulk Materials ◽

Nitrogen Doped ◽

The Core ◽

Zinc Peroxide ◽

P Type

Abstract Owing to its high technological importance for optoelectronics, zinc oxide received much attention. In particular, the role of defects on its physical properties has been extensively studied as well as their thermodynamical stability. In particular, a large concentration of Zn vacancies in ZnO bulk materials is so far considered highly unstable. Here we report that the thermal decomposition of zinc peroxide produces wurtzite-type ZnO nanoparticles with an extraordinary large amount of zinc vacancies (>15%). These Zn vacancies segregate at the surface of the nanoparticles, as confirmed by ab initio calculations, to form a pseudo core-shell structure made of a dense ZnO sphere coated by a Zn free oxo-hydroxide mono layer. In others terms, oxygen terminated surfaces are privileged over zinc-terminated surfaces for passivation reasons what accounts for the Zn off-stoichiometry observed in ultra-fine powdered samples. Such Zn-deficient Zn1-xO nanoparticles exhibit an unprecedented photoluminescence signature suggesting that the core-shell-like edifice drastically influences the electronic structure of ZnO. This nanostructuration could be at the origin of the recent stabilisation of p-type charge carriers in nitrogen-doped ZnO nanoparticles.

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EFFECT OF ELECTRIC FIELD, TEMPERATURE AND CORE DIMENSIONS IN III–V COMPOUND CORE–SHELL NANOWIRES

NANO ◽

10.1142/s1793292014500519 ◽

2014 ◽

Vol 09 (04) ◽

pp. 1450051

Author(s):

ASHWANI VERMA ◽

BAHNIMAN GHOSH ◽

AKSHAY KUMAR SALIMATH

Keyword(s):

Monte Carlo ◽

Electric Field ◽

Spin Relaxation ◽

Compound Semiconductor ◽

Core Shell ◽

Relaxation Length ◽

The Core ◽

Field Temperature ◽

Simulation Results ◽

Shell Nanowires

In this paper, we have used semiclassical Monte Carlo method to show the dependence of spin relaxation length in III–V compound semiconductor core–shell nanowires on different parameters such as lateral electric field, temperature and core dimensions. We have reported the simulation results for electric field in the range of 0.5–10 kV/cm, temperature in the range of 77–300 K and core length ranging from 2 nm to 8 nm. The spin relaxation mechanisms used in III–V compound semiconductor core–shell nanowire are D'yakonov–Perel (DP) relaxation and Elliott–Yafet (EY) relaxation. Depending upon the choice of materials for core and shell, nanowire forms two types of band structures. We have used InSb – GaSb core–shell nanowire and InSb – GaAs core–shell nanowire and nanowire formed by swapping the core and shell materials to show all the results.

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Core-Shell Structure of Intermediate Precipitates in a Nb-Based Z-Phase Strengthened 12% Cr Steel

Microscopy and Microanalysis ◽

10.1017/s1431927617000174 ◽

2017 ◽

Vol 23 (2) ◽

pp. 360-365 ◽

Cited By ~ 6

Author(s):

Masoud Rashidi ◽

Hans-Olof Andrén ◽

Fang Liu

Keyword(s):

Phase Transformation ◽

Shell Structure ◽

Atom Probe Tomography ◽

Atom Probe ◽

Core Shell ◽

The Core ◽

The Matrix ◽

Core Shell Structure ◽

Cr Steels

AbstractIn creep resistant Z-phase strengthened 12% Cr steels, MX (M=Nb, Ta, or V, and X=C and/or N) to Z-phase (CrMN, M=Ta, Nb, or V) transformation plays an important role in achieving a fine distribution of Z-phase precipitates for creep strengthening. Atom probe tomography was employed to investigate the phase transformation in a Nb-based Z-phase strengthened trial steel. Using iso-concentration surfaces with different concentration values, and subtracting the matrix contribution enabled us to reveal the core-shell structure of the transient precipitates between MX and Z-phase. It was shown that Z-phase forms by diffusion of Cr into NbN upon ageing, and Z-phase has a composition corresponding to Cr1+xNb1−xN with x=0.08.

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The role of diffusion behavior on the formation and evolution of the core‐shell structure in BaTiO 3 ‐based ceramics

Journal of the American Ceramic Society ◽

10.1111/jace.16735 ◽

2019 ◽

Vol 103 (1) ◽

pp. 304-314 ◽

Cited By ~ 2

Author(s):

Cheng Chen ◽

Hua Hao ◽

Jingjing Cui ◽

Cong Yu ◽

Yingfei Tang ◽

...

Keyword(s):

Shell Structure ◽

Core Shell ◽

Diffusion Behavior ◽

The Core ◽

Formation And Evolution ◽

Core Shell Structure

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

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.11.165 ◽

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.

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Nanoparticle@MoS2 Core–Shell Architecture: Role of the Core Material

Chemistry of Materials ◽

10.1021/acs.chemmater.8b01333 ◽

2018 ◽

Vol 30 (14) ◽

pp. 4675-4682 ◽

Cited By ~ 16

Author(s):

Jennifer G. DiStefano ◽

Yuan Li ◽

Hee Joon Jung ◽

Shiqiang Hao ◽

Akshay A. Murthy ◽

...

Keyword(s):

Core Material ◽

Core Shell ◽

The Core

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Toughening of PBT/PC blends with epoxy functionalized core-shell modifiers

e-Polymers ◽

10.1515/epoly.2009.9.1.939 ◽

2009 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Fangfang Zhang ◽

Shulin Sun ◽

Xiaoyun Liu ◽

Lixia Zhang ◽

Huixuan Zhang

Keyword(s):

Electron Microscopy ◽

Glycidyl Methacrylate ◽

Core Shell ◽

Bisphenol A Polycarbonate ◽

Elongation At Break ◽

The Core ◽

Transmission Electron ◽

Partially Miscible ◽

The Matrix ◽

Izod Impact

AbstractCore-shell modifiers of MB-g-GMA have been synthesized by emulsion polymerization technique. For these modifiers, the core is made up of the crosslinked poly(butadiene) and the shell is methyl methacrylate (MMA) and glycidyl methacrylate (GMA) copolymer. These modifiers were used to toughen poly(butylene terephthalate) (PBT)/bisphenol A polycarbonate (PC) blends. The mechanical properties showed that the addition of 15% MB-g-GMA had a very good influence on the notched Izod impact strength and elongation at break of the PBT/PC blends. DMA results showed PBT was partially miscible with PC and the addition of MB-g-GMA further improved the miscibility of PBT and PC. DSC tests further testified the introduction of MB-g-GMA improved miscibility between PBT and PC. Scanning electron microscopy (SEM) displayed a very good dispersion of MB-g-GMA particles in PBT/PC blend. Transmission electron microscopy (TEM) proved MB-g-GMA particles were enveloped by a thin layer of PC, PBT and PC showed co-continuous structure or dispersed phase which depended on the content of MB-g-GMA. SEM results showed shear yielding of the matrix and cavitation of rubber particles were the major toughening mechanisms.

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