Reactions of azomethane on a clean, H-covered, and O-covered Pt(111) surface

The reactions of azomethane were studied on a clean, H-covered, and O-covered Pt(111) surface at different coverages of azomethane, and ratios of hydrogen or oxygen to azomethane, by temperature programmed desorption. On a clean surface, dehydrogenetion, together with breaking of the NN bond to produce HCN and H₂ were the major reactions. Small amounts of methylamine and cyanogen were also observed. On an H-covered surface at high hydrogen coverage, methane was the dominant product, in addition to H₂. This adsorbed hydrogen promoted breaking of the CN bond. In addition, the dehydrogenation product HCN was also observed, as was methylamine. On the O-covered surface, CO, CO₂, H₂O, and small amounts of NO were observed together with the products typical for a clean surface. Comparison of the results with those for acetylene, ethylene, and diazomethane is made.