Metallic Technetium Sequestration in Nickel Core/Shell Microstructure during Fe(OH)2 Transformation with Ni doping

Near infrared (NIR) absorbing nanoparticles synthesized by the reduction of HAuCl4 with Na2S exhibited absorption bands at ∼530 nm, and in the NIR region of 650–1100 nm. The NIR optical properties were not found to be related to the earlier proposed Au2S–Au core-shell microstructure in previous studies. From a detailed study of the structure and microstructure of as-synthesized particles in this work, S-containing, Au-rich, multiply-twinned nanoparticles were found to exhibit NIR absorption. They consisted of amorphous AuxS (where x = 2), mostly well mixed within crystalline Au, with a small degree of surface segregation of S. Therefore, NIR absorption was likely due to interfacial effects on particle polarization from the introduction of AuxS into Au particles, and not the dielectric confinement of plasmons associated with a core-shell microstructure.

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CO2 Methanation over Ni/Al@MAl2O4 (M = Zn, Mg, or Mn) Catalysts

Catalysts ◽

10.3390/catal9070599 ◽

2019 ◽

Vol 9 (7) ◽

pp. 599 ◽

Cited By ~ 9

Author(s):

Le ◽

Kim ◽

Jeong ◽

Park

Keyword(s):

Surface Oxidation ◽

Catalytic Performance ◽

Precipitation Method ◽

Core Shell ◽

Ni Doping ◽

Ni Catalysts ◽

Co2 Methanation ◽

Temperature Programmed ◽

Diffuse Reflectance Infrared ◽

Spinel Structures

In this study, unique core-shell aluminate spinel supports, Al@MAl2O4 (M = Zn, Mg, or Mn), were obtained by simple hydrothermal surface oxidation and were applied to the preparation of supported Ni catalysts for CO2 methanation. For comparison, CO methanation was also evaluated using the same catalysts. The prepared catalysts were characterized with a variety of techniques, including N2 physisorption, CO2 chemisorption, H2 chemisorption, temperature-programmed reduction with H2, temperature-programmed desorption of CO2, X-ray diffraction, high-resolution transmission electron microscopy, and in-situ diffuse reflectance infrared Fourier transform spectroscopy. The combination of supports with core-shell spinel structures and Ni doping with a deposition–precipitation method created outstanding catalytic performance of the Ni catalysts supported on Al@MgAl2O4 and Al@MnAl2O4 due to improved dispersion of Ni nanoparticles and creation of moderate basic sites with suitable strength. Good stability of Ni/Al@MnAl2O4 catalyst was also confirmed in the study.

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Core/Shell Microstructure Induced Synergistic Effect for Efficient Water-Droplet Formation and Cloud-Seeding Application

ACS Nano ◽

10.1021/acsnano.7b06114 ◽

2017 ◽

Vol 11 (12) ◽

pp. 12318-12325 ◽

Cited By ~ 9

Author(s):

Yanlong Tai ◽

Haoran Liang ◽

Abdelali Zaki ◽

Nabil El Hadri ◽

Ali M. Abshaev ◽

...

Keyword(s):

Synergistic Effect ◽

Water Droplet ◽

Droplet Formation ◽

Core Shell ◽

Shell Microstructure ◽

Cloud Seeding

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Characterization of core-shell microstructure and self-healing performance of electrospun fiber coatings

Polymer ◽

10.1016/j.polymer.2016.10.062 ◽

2016 ◽

Vol 107 ◽

pp. 263-272 ◽

Cited By ~ 32

Author(s):

Thu Q. Doan ◽

L. Suzanne Leslie ◽

Sang Yup Kim ◽

Rohit Bhargava ◽

Scott R. White ◽

...

Keyword(s):

Electrospun Fiber ◽

Core Shell ◽

Self Healing ◽

Shell Microstructure ◽

Fiber Coatings

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Ultrahigh coercivity and core–shell microstructure achieved in oriented Nd–Fe–B thin films diffusion-processed with Dy-based alloys

Applied Physics A ◽

10.1007/s00339-016-0709-0 ◽

2017 ◽

Vol 123 (1) ◽

Cited By ~ 4

Author(s):

Tongbo Zhang ◽

Xiaoqian Zhou ◽

Dedong Yu ◽

Yanqing Fu ◽

Guojian Li ◽

...

Keyword(s):

Thin Films ◽

Core Shell ◽

Shell Microstructure

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Insight into the Effect of the Core–Shell Microstructure on the Electrochemical Properties of Undoped 3D-Networked Conductive Diamond/Graphite

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.8b11865 ◽

2019 ◽

Vol 123 (10) ◽

pp. 6018-6029 ◽

Cited By ~ 1

Author(s):

Zhaofeng Zhai ◽

Nan Huang ◽

Bing Yang ◽

Chun Wang ◽

Lusheng Liu ◽

...

Keyword(s):

Electrochemical Properties ◽

Core Shell ◽

Shell Microstructure ◽

The Core ◽

Insight Into

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Synthesis and Mechanical Characterization of a Ti(C,N)/Mo–Co–Ni/CaF2@Al2O3 Self-Lubricating Cermet

Materials ◽

10.3390/ma12233981 ◽

2019 ◽

Vol 12 (23) ◽

pp. 3981

Author(s):

Chuanhao Li ◽

Mingdong Yi ◽

Gaofeng Wei ◽

Chonghai Xu

Keyword(s):

Diffusion Mechanism ◽

Core Shell ◽

Material System ◽

Sintering Process ◽

Shell Microstructure ◽

Nanocomposite Powder ◽

Cermet Material ◽

Temperature Liquid ◽

Hot Pressing Sintering

In this paper, an Al2O3 coated CaF2 (CaF2@Al2O3) nanocomposite powder is used as the additive phase of a Ti(C,N)-based self-lubricating cermet material. A novel self-lubricating ceramic material with a multilayer core–shell microstructure was prepared using a vacuum hot-pressing sintering process. The results show that the surface of the CaF2 powder is coated with Al2O3, and when introduced into a Ti(C,N)–Mo–Co–Ni material system, it can utilize the high-temperature liquid phase diffusion mechanism of the metal Mo–Co–Ni phase in the sintering process. The CaF2@Al2O3@Mo–Co–Ni multilayer core–shell microstructure is formed in the material. Compared with the direct addition of CaF2 and Al2O3, the hardness and fracture toughness of the material are increased by 24.31% and 22.56%, reaching 23.93 GPa and 9.94 MPa·m1/2, respectively. The formation of the multilayer core–shell microstructure is the main reason for the improvement of the mechanical properties of the material.

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Microstructure in Pressureless-Sintered Iron-Containing Hydroxyapatite/Titanium Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.1582 ◽

2010 ◽

Vol 160-162 ◽

pp. 1582-1587 ◽

Cited By ~ 1

Author(s):

Qing Chang ◽

Hong Qiang Ru ◽

Dao Lun Chen

Keyword(s):

Low Temperature ◽

Biomedical Applications ◽

Core Shell ◽

Pressureless Sintering ◽

Shell Microstructure ◽

Sintered Iron ◽

The Core ◽

Reinforcing Particles ◽

New Type ◽

Core Shell Structure

Pure hydroxyapatite (HA) is brittle and it cannot be directly used for the load-bearing biomedical applications. Aim of this paper was to present a new iron-containing hydroxyapatite/titanium composites synthesized via pressureless sintering at a relatively low temperature of 1000°C using nano-sized HA powders and Ti-33%Fe mixed powders. The microstructure and composition of the new type composites were evaluated. The results showed that the uniformly distributed reinforcing particles had a unique and favorable core/shell microstructure after sintering that consisted of outer titanium and inner iron. The mechanism for the formation of the core/shell structure was discussed. The addition of iron reduced the decomposition rate of HA and the interaction between HA and titanium.

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