Transmission electron microscopy specimen preparation methods

Speciman Preparation for Transmission Electron Microscopy of Materials (J. C. Brauman, R. M. Anderson, and M. L. McDonald, eds.) MRS Symp. Proc vol. 115, Materials Research Society, Pittsburg, 1988. This conference proceedings contains many up-to-date methods as well as references to books on various aspects of specimen preparation. 

Glauert AM, Lewis PR (1998) Biological Specimen Preparation for Transmission Electron Microscopy. In Glauert AM (ed). Practical Methods in Electron Microscopy, vol 17. Portland Press, London... 

Transmission electron microscopy (TEM) can provide valuable information on particle size, shape, and structure, as well as on the presence of different types of colloidal structures within the dispersion. As a complication, however, all electron microscopic techniques applicable for solid lipid nanoparticles require more or less sophisticated specimen preparation procedures that may lead to artifacts. Considerable experience is often necessary to distinguish these artifacts from real structures and to decide whether the structures observed are representative of the sample. Moreover, most TEM techniques can give only a two-dimensional projection of the three-dimensional objects under investigation. Because it may be difficult to conclude the shape of the original object from electron micrographs, additional information derived from complementary characterization methods is often very helpful for the interpretation of electron microscopic data. 

The use of transmission electron microscopy in heterogeneous catalysis centers around particle size distribution measurement, particle morphology and structural changes in the support. Consideration is given to the limitations of conventional electron microscopy and how modifications to the instrument enable one to conduct in-situ experiments and be in a position to directly observe many of the features of a catalyst as it participates in a reaction. In order to demonstrate the power of the in-situ electron microscopy technique examples are drawn from areas which impact on aspects of catalyst deactivation. In most cases this information could not have been readily obtained by any other means. Included in this paper is a synopsis of the methods available for preparing specimens of model and real catalyst systems which are suitable for examination by transmission electron microscopy. 

Belkoura, L., Stubenrauch, C. and Strey, R. (2004) Freeze fracture direct imaging A new freeze fracture method for specimen preparation in cryo-transmission electron microscopy. 

Transmission Electron Microscopy. A Philips model 201 (Arvada, CO) transmission electron microscope was used as an alternative method for determining the particle sizes of Ludox silicas. Specimens were prepared on formvar-coated, 200-mesh copper specimen grids. Typical acceleration voltages and magnifications were 80 kV and 65,000X. 

Transmission electron microscopy (TEM) is a powerful technique that is used to determine the microstructure of materials at very high resolution (2-10 nm size). Because the technique requires a very thin specimen, special sample preparation methods have been developed such as ultramicrotomy and ion milling. 

One of the main tasks of nuclear-reactor safety research is assessing the integrity of the reactor pressure vessel (RPV). The properties of RPV steels and the influences of thermal and neutron treatments on them are routinely investigated by macroscopic methods such as Charpy V-notch and tensile tests. It turns out that the embrittlement of steel is a very complex process that depends on many factors (thermal and radiation treatment, chemical compositions, conditions during preparation, ageing, etc.). A number of semi-empirical laws based on macroscopic data have been established, but unfortunately these laws are never completely consistent with all data and do not yield the required accuracy. Therefore, many additional test methods are needed to unravel the complex microscopic mechanisms responsible for RPV steel embrittlement. Our study is based on experimental data obtained when positron annihilation spectroscopy (PAS) and Mdssbauer spectroscopy (MS) were applied to different RPV steel specimens, which are supported by results from transmission electron microscopy (TEM) and appropriate computer simulations. 

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