Room-Temperature Propylene Dehydrogenation and Linear Atomic Chain Formation on Ni(111)

The structures formed by propylene adsorption on Ni(111) at room temperature are determined by a combination of scanning tunneling microscopy and density functional theory. As a result of the interaction with the Ni(111) surface, propylene molecules are dehydrogenated and coupled into linear hydrocarbon chains. The length of the chains varies from 8 to 60 Å, with the most frequently observed length of 18 Å. At saturated coverage, some chains are closed in rings with a diameter of 6 Å. A C12H12 model is proposed for most often observed chains. We demonstrate the possibility of combining initial propylene molecules into chains after dehydrogenation of the CH3 fragment.