Reactive gold thin films grown on iridium

We report results of our studies on the dissociative adsorption of hydrogen on Au thin films grown epitaxially on Ir{1 1 1} surface, using nuclear reaction analysis. We found that H2 dissociatively adsorbs on these Au{1 1 1} films. This feature can be contrasted to the well-known noble bulk Au surfaces, which do not dissociate hydrogen molecules. We attribute this to the local surface properties, e.g., electron localization (the narrowing of the s-band, the s-band center model), which can explain the unexpected high reactivity of a thin Au{1 1 1} film.