Quantitative Characterization of Internal Boundaries — What Can Be Achieved with Electron Microscopy?

2001 ◽  
Vol 7 (S2) ◽  
pp. 236-237
Author(s):  
Christian Elsasser ◽  
Manfred Rühle

Internal boundaries in crystalline microstructures, like polycrystals, thin-film or multi-layer composites, essentially control many important material properties and physical phenomena, such as mechanical deformation and fracture, transport processes or phase transformations. This influence is originating from the local atomistic and electronic structures at the boundaries. Hence, for a. science-based technological design and optimisation of structural and functional materials it is of paramount importance to characterize and understand the structure, chemistry and bonding at interfaces.Transmission electron microscopy (TEM) has matured to one of the most successful experimental approaches for the analysis of extended structural defects like dislocations and interfaces. This presentation discusses scientific and technological ingredients of TEM for quantitative characterisations on the microscopic level. For selected model cases of internal interfaces it illustrates recent achievements of both experiment and theory. A variety of interface properties and corresponding TEM techniques for their characterisation are summarized in TABLE 1.

2014 ◽  
Vol 661 ◽  
pp. 8-13 ◽  
Author(s):  
Intan Syaffinazzilla Zaine ◽  
N.A.M. Napiah ◽  
Azmi Mohamad Yusof ◽  
A.N. Alias ◽  
A.M.M. Ali ◽  
...  

The MWCNTs was functionalized by refluxing commercial MWCNTs (a-MWCNTs) in concentrated HNO3/H2SO4 (3:1 v/v) at 100°C for 6 hours. The dispersion of a-MWCNTs and functionalized MWCNTs (f-MWCNTs) were observed after 1 hour sonication in ethanol. Both samples were characterized by UV-vis spectroscopy for dispersion behavior. The dried f-MWCNTs and a-MWCNTs were characterized by Raman spectroscopy to estimate the defect level. The morphology of the samples were analyzed by Transmission Electron Microscopy (TEM). The f-MWCNTs was well dispersed in ethanol within 2 weeks of observations period. The colloidal stability of a-MWCNTs was low as it was easily sediment after 24 hours. The UV-vis spectra of f-MWCNTs show maximum absorbance at 250 nm meanwhile no absorbance was observed for a-MWCNTs. Analysis from Raman spectrum shows that the f-MWCNTs have relative intensity of 1.101 which is higher than a-MWCNTs that have relative intensity of 0.935. The image from TEM revealed that the f-MWCNTs have structural defects and the absence of amorphous carbon on sidewall meanwhile the a-MWCNTs indicate otherwise.


2012 ◽  
Vol 84 (15) ◽  
pp. 6312-6316 ◽  
Author(s):  
Lin-Ai Tai ◽  
Yu-Ting Kang ◽  
Yu-Ching Chen ◽  
Yu-Chao Wang ◽  
Yu-Jing Wang ◽  
...  

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