Microscopy investigations of the microstructural change and thermal response of cobalt-based nanoparticles confined inside a carbon nanotube medium

Ceria nanoparticles supported on aligned carbon nanotubes (CeO2/ACNTs), a novel adsorbent for fluoride from drinking water, were prepared by chemical reaction of CeCl3 with NaOH on aligned carbon nanotube solution and subsequent heat treatment. The best fluoride adsorption effect of CeO2/ACNTs occurs at pH 4.0 ~ 9.0. The largest adsorption capacity of CeO2/ACNTs reaches 33.7 mg g-1 at an equilibrium fluoride concentration of 18.0 mg l-1 at pH 7.0. The experiment results suggest that CeO2/ACNTs have great potential applications in environmental protection.

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Carbon Nanotube Fiber Pretreatments for Electrodeposition of Copper

Advances in Materials Science and Engineering ◽

10.1155/2018/3071913 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Pyry-Mikko Hannula ◽

Minttu Junnila ◽

Dawid Janas ◽

Jari Aromaa ◽

Olof Forsén ◽

...

Keyword(s):

Heat Treatment ◽

Carbon Nanotube ◽

Boric Acid ◽

Electrochemical Deposition ◽

Electrochemical Impedance ◽

Copper Deposition ◽

High Resistivity ◽

Active Surface Area ◽

Carbon Nanotube Fiber ◽

Watts Bath

There is increasing interest towards developing carbon nanotube-copper (CNT-Cu) composites due to potentially improved properties. Carbon nanotube macroscopic materials typically exhibit high resistivity, low electrochemical reactivity, and the presence of impurities, which impede its use as a substrate for electrochemical deposition of metals. In this research, different CNT fiber pretreatment methods, such as heat treatment, immersion in Watts bath, anodization, and exposure to boric acid (H3BO3), were investigated to improve the electrochemical response for copper deposition. It was shown that these treatments affect the surface activity of CNTs, including electrical resistivity, polarization resistance, and active surface area, which influence the electrodeposition process of copper. Properties of CNT structures and CNT-Cu composites were researched by electrochemical impedance spectroscopy (EIS), galvanostatic copper deposition, scanning electron microscope (SEM), and four-point electrical resistance measurements. Heat treatment, Watts bath, anodization, and boric acid treatments were shown to be effective for modifying the CNT surface reactivity for subsequent electrochemical deposition of copper.

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Effect of Second Phase After-Heat Treatment on the Thermal Conductivity of AlN Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.403.61 ◽

2008 ◽

Vol 403 ◽

pp. 61-63

Author(s):

Hyeon Keun Lee ◽

Do Kyung Kim

Keyword(s):

Thermal Conductivity ◽

Heat Treatment ◽

Rate Control ◽

Microstructural Characterization ◽

Nitrogen Atmosphere ◽

Microstructural Change ◽

High Thermal Conductivity ◽

Major Influence ◽

Second Phase ◽

High Electrical Resistivity

The high thermal conductivity of Aluminum nitride, coupled with its high electrical resistivity and nontoxic nature, makes it a very promising material for electronic substrate. In this study, microstructural characterization on the thermal conductivity of AlN ceramics was investigated. An AlN ceramic was prepared with a dopant Y2O3 under a reducing nitrogen atmosphere with carbon. In order to obtain high thermal conductivity, cooling rate control and after-heat treatment was carried out. Morphology of the second phase was characterized using scanning electron microscopy (SEM). SEM studies showed that the microstructural change caused by after-heat treatment have a major influence on the thermal conductivity.

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