The chemical properties of catalysts often depend on the size, shape and structure of the supported metal particles. To characterize these morphological features and relate them to catalysis is one of the main objectives for HREM study of catalysts. However, in plan view imaging, details of the shape and structure of ultra-fine supported particles (<2nm) are often obscured by the overlapping contrast from the support, and supported sub-nanometer particles are sometimes even invisible. Image simulations may help in the interpretation at HREM images of supported particles in particular to extract useful information about the size, shape and structure of the particles. It should also be a useful tool for evaluating the imaging conditions in terms of visibility of supported particles. P. L. Gai et al have studied contrast from metal particles supported on amorphous material using multislice simulations. In order to better understand the influence of a crystalline support on the visibility and apparent morphological features of supported fine particles, we have calculated images of Pt and Re particles supported on TiO2(rutile) in both plan view and profile view.
A Wide-Band Circularly Polarized Wide-Gap Antenna Loaded with a Y-Shaped Metal Strip for L-Band Application