A novel approach is being used for the study of interfaces between small metal crystallites and oxides. The metal crystallites are supported on submicron oxide particles of simple geometric shape. Using nonporous oxides limits the location of the metal to the exterior of the oxide; therefore, profile and projected views of the metal crystallites can be readily obtained in a transmission electron microscope. These views permit determination of technologically important parameters, such as contact angles, wetting and spreading of the metal, and forces of attraction between the metal and oxide. Registry of the atomic planes at the interface and nucleation site identification can also be observed. The relatively high surface area permits reactivity studies to be performed on these catalysts at standard reaction pressures. Thus, the information obtained has considerable impact on the study of metal-support interactions in heterogeneous catalysis and in the study of metal-oxide bonding in ceramic science. This fundamental information has great value in a number of important technologies including protective coatings, brazing fluxes, composite materials, metal-semiconductor contacts in integrated circuits, corrosion of metals, sintering of composites and catalysts, and support effects on heterogeneous catalysts.
