Transmission Electron Microscopy Imaging & Diffraction- Class Report

Rajasekarakumar Vadapoo Department of Physics, University of Puerto Rico,PR-00931,USA. R More info: http://nanophysics.wordpress.com

Imaging and diffraction. Aim: To have a hands ds on experience on imaging and diffraction in Transmission Electron Microscopy (TEM) and to analyse the results.

Experimental details: The experiments were carried out in Carl Zeiss 200 keV TEM. The sample used for analysis are silver nanoparticles and MoO3 single crystal.

Results and Discussion:
Imaging of Ag nanoparticles: nanoparticles Fig.1. shows the Transmission Electron Microscopy image of Ag nanoparticles. Fig. 2. Shows the area of image where the nanoparticles are distributed uniformly. Fig.3. shows the nanoparticle size around 30 nmnm 60 nm range.

Fig. 1. TEM of Ag Nanoparticle

Fig. 2. Area of uniform distribution of nanoparticles

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Fig.3. image shows that the Nanoparticle around 30 30-60nm.


Diffraction of Ag nanoparticles:

Fig.4. shows theDiffraction patter of Ag nanoparticles shown in fig.2. at different Camera Length. The fig.4. shows the electron diffraction pattern of the silver Nanoparticles shown in fig.2 at different camera length. As we seen the diffraction patterns pattern show w the polycrystalline nature which make sense. If we closely look at Fig. 2 it shows several nanoparticles of Ag which randomly oriented in the grid gives the polycrystalline patterns. The observed single Nanoparticle is single crystal in nature as we have seen there are no grain boundaries.

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Imaging of MoO3 Single crystal sample: From the fig. 5. we can see the facet of the single crystal MoO3 and the corresponding diffraction pattern is shown in fig.6.

Fig.5. The TEM image of single crystalline MoO3 crystal.


Diffraction pattern of Single crystal:

Fig.6. TEM diffraction pattern of single crystalline MoO3 taken at the camera Length 300 mm.

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The crystal structure of MoO3 is BCC. The fig.6. shows the diffraction pattern (DP) of the single crystalline MoO3. From the DP we can say that the viewing direction is [001] & the corresponding ZOLZ pattern can be indexed.

Conclusion: The transmission electron microscopy images and its corresponding diffraction pattern have been taken using carl Zeiss 200 keV TEM for nanoparticles and single crystal samples, then the corresponding results have been discussed.

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