In situ Electron microscopy studies

In-Situ Electron Microscopy Studies of the Palladium/Alumina-Oxygen System... 

IN-SITU ELECTRON MICROSCOPY STUDIES OF CATALYST DEACTIVATION... 

The in-situ electron microscopy studies presented here were performed either in a JEM 120 instrument fitted with an AGI gas reaction cell or a modified JEOL 200CX TEM/STEM microscope equipped with a custom designed environmental cell which accommodates a heating stage. With this latter instrument it is possible to obtain detailed information concerning the chemical state of the specimen under reaction conditions via in-situ electron diffraction analysis. 

In situ electron microscopy studies were performed with overlapping thin films of nickel and titanium dioxide. A nickel film approximately 30 nm thick was prepared by vacuum deposition of the metal onto a single crystal of sodium chloride. The salt was dissolved in distilled water, and the residual metal film was... 

Baker, R.T.K., In situ electron microscopy studies of catalyst particle behavior, Catal.Rev.-Sci.Eng. 19(2), 161-209(1979). 

Crystal Morphology Crystal morphology determines the mechanical properties, the biodegradability, and the biocompatibility of polymers. Thus, it is necessary to understand the mechanism of polymer crystallization in order to control the polymer microstructure and, thereby, its properties. The crystallinity and cavitation of polymers have been studied using optical and in situ electron microscopy as complementary techniques, among many others. 

Ross, F. M. (2001), Dynamic studies of semiconductor growth processes using in situ electron microscopy, MRS Bulletin 26, 94-101. 

STM, X-ray reflectivity, and AFM are excellent in situ techniques for studying surface topography and morphology. Scanning electron microscopy is a useful ex situ technique. 

Another approach is to perform ex situ reactions and insert the sample into a high vacuum system without exposure to ambient conditions. Incorporating N2 glove boxes or reactor systems with X-ray photoelectron spectroscopy (XPS) sample handling can also provide information that is closer to operational conditions. In a similar manner ex situ reactions and sample handling are starting to be apphed to electron microscopy studies. Commercially available sample transfer systems will accelerate the application of this methodology. 

It is noteworthy that the d- values obtained from the electron microscopy experiments are definitely different from those obtained by in situ neutron scattering studies of the gel phase, being much higher for both the c = 0.001 M and c = 0.01 M cases. As we saw in Chapters 1 and 3, the spacings reported for these electrolyte concentrations were 60 nm and 30 nm, respectively, which have to be compared with the present results. The electron microscopy results are greater by a factor between one and a half and two, the discrepancy being outside the range of experimental error. 

Using the accumulated data obtained from in-situ and high resolution electron microscopy studies, Baker and co-workers (ref. 22) developed a model to account for the growth of filamentous carbon resulting from metal catalyzed decomposition of selected hydrocarbons. The main steps in the mechanism are adsorption and decomposition of hydrocarbons at the leading face of catalyst particle, followed by dissolution of carbon in the metal and diffusion to the trailing faces where carbon is precipitated from solution to form the filament. Deactivation of the catalyst occurs... 

Wang LM, Ewing RC (1992c) Ion beam-induced amorphization of (Mg,Fe)2Si04 ohvine series An in situ transmission electron microscopy study. Mater Res Soc Symp Proc 235 333-338... 

Qian, D. and Dickey, E. C. In-situ transmission electron microscopy studies of polymer-carbon nanotube composite deformation. JMictvsc., 204, 39-45 (2001). 

Tan, X, and Shangy, J.K (2002) In-situ transmission electron microscopy study of electric-field-induced grain-boundary cracking in lead zirconate titanate. Philos. Mag. A, 82, 1463-1478. 

Punning A, Vunder V, Must I, lohanson U, Anbaijaferi G, Aabloo A (2016). In situ scanning electron microscopy study of strains of ionic electroadive polymer actuators. J Intell Mater Syst Struct 27(8) 1061-1074... 

Liu XH et al (2011) Revtrsible nanopoie fmmation in Ge nanowiies during lithiation— delithiation cycling an in situ transmission electron microscopy study. Nano Lett 11 3991—... 

Olynick, D.L., Gibson, J.M. and Averback, R.S. (1995) In situ ultra-high vacuum transmission electron microscopy studies of nanocrystalline copper. Materials Science and Engineering A, A204, 54-8. 

In contrast to many other surface analytical techniques, like e. g. scanning electron microscopy, AFM does not require vacuum. Therefore, it can be operated under ambient conditions which enables direct observation of processes at solid-gas and solid-liquid interfaces. The latter can be accomplished by means of a liquid cell which is schematically shown in Fig. 5.6. The cell is formed by the sample at the bottom, a glass cover - holding the cantilever - at the top, and a silicone o-ring seal between. Studies with such a liquid cell can also be performed under potential control which opens up valuable opportunities for electrochemistry [5.11, 5.12]. Moreover, imaging under liquids opens up the possibility to protect sensitive surfaces by in-situ preparation and imaging under an inert fluid [5.13]. 

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