Oxide Structures formed on Silver Single Crystals due to Hyperthermal Atomic Oxygen Exposure
ABSTRACTSilver (100) and (111) single crystals were exposed to a unique laser detonation atomic oxygen source, which produces a high flux of 5 eV atomic oxygen, for seven hours at 220°C. The resultant oxide and oxide-metal interfaces were characterized by optical, scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HREM). The oxide scale was more than 10-micron thick and very weakly attached to the Ag substrate. The silver oxides were complex and surprising, differ in their thickness and the oxide phases due to the orientation of the Ag single crystals. The cross-section TEM studies revealed complex microstructures with many defects, such as micro-twins, porosity and irregular shaped grains.