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

Abstract

In our previous studies, we have developed a wet process to synthesize a copper-single walled carbon nanotube (Cu-SWCNT) metal nanocomposite with excellent mechanical properties. The nanostructure of this Cu-SWCNT composite was confirmed independently by energy-dispersive X-ray spectroscopy mapping, spectroscopy measurements, and Transmission Electron Microscope (TEM) images with discernable SWCNT clusters in nano sizes. However, TEM images with discernable nano-sized SWCNT clusters are rare. In this paper, we present analysis of indirect TEM image patterns, such as moiré fringes, to infer the existence of SWCNT clusters within the copper matrix. Moiré fringes or patterns in the TEM images of a Cu-SWCNT nanocomposite could be generated due to the overlapping of more than one thin crystals with similar periodic arrangements of atoms, promoted by SWCNT clusters. However, the presence of moiré patterns is not a sufficient or a necessary condition for the existence of SWCNT clusters. It was found that based on the overlapping angle of two periodic arrangements, it is feasible to distinguish the moiré fringes induced by SWCNT clusters from those by other factors, such as dislocations. The ability to identify SWCNTs within the copper matrix based on indirect TEM moiré patterns helps to widen the usability of TEM images.

Reversed Phase Transformation of β→α-Sn at Elevated Temperatures towards Quantum Material Integration on Silicon

“…[33][34][35] Panels (d) and (e) show an α-Sn(111) inter-planar spacing of d=(0.367 ± 0.03) nm, in good agreement with the expected value of 0.370 nm for 4.2 at.% Ge and -0.63% in-plane compressive strain measured by XRD. Moiré patterns 46,47 are also observed in some regions (see Panel (f)-(h)) due to the vertical overlapping of the predominant α-Sn(111) planes with β-Sn(200) planes at an angle of ∼11.5°. In contrast, panels (i)-(k) shows a pure β-Sn microdot with its (101) planes almost parallel to the surface of the Si substrate.…”

Advances in Thermochemical Synthesis and Characterization of the Prepared Copper/Alumina Nanocomposites

“…Additionally, in Figure 5b, Moire fringes could be observed. According to [37] inside a single copper crystal, the clusters of Al2O3 particles could considerably alter the surrounding lattice structure, enough to prompt formation of Moire fringes. In Figure 6a, besides the spots corresponding to copper, additional diffraction spots are visible, indicating presence of a solid solution.…”

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

“…The readers should refer to [8][9][10] for comprehensive review of the LSI process versus the dry process, as well as the nano-structure of the Cu-SWCNT nanocomposite synthesized by the LSI process.…”

“…Due to the small size of the Cu-SWCNT nanocomposite and it being an implant onto a pure copper substrate, the sample is not homogeneous, required by the standard tensile test. However, TEM images with discernable nano-sized SWCNT clusters are rare, the analysis of indirect TEM image patterns, such as moiré fringes, to infer the existence of SWCNT clusters within the copper matrix was presented in [10]. Moiré fringes or patterns in the TEM images of a Cu-SWCNT nanocomposite could be generated due to the overlapping of two or more thin crystals with similar periodic arrangements of atoms, promoted by SWCNT clusters.…”