TEM Nano-Moiré Pattern Analysis of a Copper/Single Walled Carbon Nanotube Nanocomposite Synthesized by Laser Surface Implanting

In our previous studies, we have developed a wet process, denoted as laser surface implanting (LSI), to synthesize a copper/single-walled carbon nanotube (Cu–SWCNT) metal nanocomposite. The nanostructure of this Cu–SWCNT composite was shown to contain discernable SWCNT clusters in nanosizes inside the copper matrix. Its hardness could achieve up to three times that of pure copper, verified by micro-hardness and nano-hardness tests. A focus ion beam bombardment test and a plane strain compression test show 2.5 times toughness improvement for the Cu-SWCNT composite. Based on these strength improvements, two potential applications for the Cu-SWCNT nanocomposite are proposed and their feasibilities are verified using specially design test rigs. The first application is related to creating long lasting electric contacts. The result shows that the Cu-SWCNT nanocomposite is highly wear-resistant. The contact area of the simulated electric contacts increases after repeated impact loading, which potentially could lower the contact resistance. The second application is to use the Cu-SWCNT implants as high strength spot weld for joining copper foils. A smaller weld with a higher strength reduces the power requirement of the laser and, consequently, the thermal distortion for higher-dimensional precision. The specially designed test rig for the weld strength characterization is a new contribution, providing a new testing capability for small and non-homogeneous samples not suitable for a standard tensile test machine.

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Molecular dynamics modeling and simulation of water desalination through a double-walled carbon nanotube with moiré pattern

Journal of Micromechanics and Molecular Physics ◽

10.1142/s2424913021420042 ◽

2022 ◽

pp. 1-9

Author(s):

Xuan Hu ◽

Shaofan Li

Keyword(s):

Molecular Dynamics ◽

Carbon Nanotube ◽

Water Permeability ◽

Water Desalination ◽

Dynamics Modeling ◽

Promising Alternative ◽

Single Walled Carbon Nanotube ◽

Moire Pattern ◽

Moiré Pattern ◽

Molecular Dynamics Modeling

Freshwater scarcity has emerged as a major challenge of our time. Under this context, the importance of an efficient and energy-saving water desalination method is highlighted. In recent years, carbon nanotube (CNT) membrane characterizing with high permeability has attracted much attention in research, and it is regarded as a promising alternative to the conventional reverse osmosis technology. This work aims at numerically investigating the water desalination ability of a novel type of CNT membrane structure, namely the double-walled carbon nanotube (DWCNT) with Moiré pattern. After establishing the physical CNT models and running the molecular dynamics (MD) simulation of the water desalination system, it is found that both the single-walled carbon nanotube (SWCNT) and DWCNT can desalinate the seawater successfully while the water permeability of DWCNT is at least 18.9% higher than that of SWCNT within the same time. As far as the Moiŕe pattern adopted in this study is concerned, the water permeability of DWCNT without Moiŕe pattern is 18.6% higher than that with Moiré pattern.

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Novel Characterizations of Mechanical Properties for a Copper/Single-Walled Carbon Nanotube Nanocomposite Synthesized by Laser Surface Implanting

C – Journal of Carbon Research ◽

10.3390/c6010010 ◽

2020 ◽

Vol 6 (1) ◽

pp. 10

Author(s):

Jay F. Tu ◽

Nilesh Rajule ◽

Sang Don Mun

Keyword(s):

Mechanical Properties ◽

Carbon Nanotube ◽

Compression Test ◽

Ion Beam ◽

Pure Copper ◽

Laser Surface ◽

Micro Hardness ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon ◽

Hardness Tests

In our previous studies, we have developed a wet process, denoted laser surface implanting (LSI), to synthesize a copper/single-walled carbon nanotube (Cu–SWCNT) metal nanocomposite as an implant onto the surface of a pure copper substrate. The nanostructure of this Cu–SWCNT composite was confirmed independently by several methods, including transmission electron microscope (TEM) images, which show discernable SWCNT clusters in nano sizes inside the copper matrix. The hardness was measured by micro-hardness tests to indicate over three times hardness over that of pure copper could be achieved. In this paper, we present several unique ways to further characterize the mechanical properties of the Cu-SWCNT nanocomposite. Nano-hardness tests are first performed to confirm that hardness improvement, about three times that of pure copper, is achieved, consistent with the micro-hardness test results. A new toughness measurement based on focus ion beam (FIB) bombardment was performed to demonstrate 2.5 times toughness improvement. Finally, a new compression test rig was designed to conduct plane strain compression test for an array of Cu-SWCNT implants. The results confirmed that the Cu-SWCNT nanocomposite exhibits a stress-strain behavior consistent with the results of the hardness and FIB tests.

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