Crystallite Morphology in Gold Catalysts Obtained by Rietveld Refinement
نویسندگان
چکیده
The microstructure of gold catalysts supported on rutile was obtained by Rietveld refinement. Three-dimensional images of the crystallites were generated in real space, as well as 3-D images of the microstrain distribution in reciprocal space. These images were used to analyze the effect of the different parameters of the refinement models on the interpretation of the microstructure of the samples. The 3-D representations can be used to obtain the crystallite volume, mass, number of atoms, and specific area of the crystallites, which can be compared with the BET specific surface area of the sample measured experimentally.
منابع مشابه
IMPROVED MODELING OF RESIDUAL STRAIN/STRESS AND CRYSTALLITE-SIZE DISTRIBUTION IN RIETVELD REFINEMENT, D. Balzar, N.C. Popa, pp. 152-157
We propose two improvements to the microstructural modeling in Rietveld refinement. The first is the model that yields the complete texture-weighted strain and stress tensors as a function of crystallite orientations, as well as the average values of macroscopic strain and stress tensors for all Laue classes. Implementation in the Rietveld refinement program can be made through the set of refin...
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