||For gold catalysis research the most commonly used catalyst contain metal nanoparticle deposited on metal oxide support. Unlike the previous examples, I used Au (111) single crystal substrate to study interactions between gold and nitrobenzene, aniline, phenyl isocyanate and benzyl azide under ultra high vacuum conditions. Temperature programmed desorption (TPD), reflection absorption infrared spectroscopy (RAIRS) and density functional theory (DFT) calculations were combined to elucidate the surface thermal and photo chemistry.|
Nitrobenzene, aniline, phenyl isocyanate photo and thermal experiment display only the molecular desorption on Au (111). In the study of benzyl azide, only thermal molecular desorption was observed. However, under 365 nm UV light irradiation, new desorption peaks were found at 280 K and 310 K, respectively. By analysis of the fragmentation pattern, the possible products was phenylmethanimine and benzonitrile. RAIRS and DFT calculations somewhat support the speculation on the product.
When the surface was subject the ion gun bombardment without high temperature annealing, thermal desorption experiments of benzyl azide showed a peak at 400 K was observed to a peak. The probable product was bisbenzyl. Increasing the ion gun bombardment time, bisbenzyl yields can be enhanced.