EVIDENCE FOR NONDESTRUCTIVE ADSORPTION OF DIALKYL SULFIDES ON GOLD

The nondestructive adsorption of long chain dialkyl sulfides on gold i s reported. Self-assembled monolayers of decanethiol, didecyl disulfid e, and didecyl sulfide were prepared and characterized by XPS, grazing -angle FT-IR, wettability studies, and TOF-SIMS. The first three techn iques provide evidence that well-packed monolayers are formed. The pos itive SIMS spectrum of didecyl sulfide showed fragments that originate from intact dialkyl sulfide attached to gold without C-S bond cleavag e. Our results underline the generally accepted nondestructive adsorpt ion process of dialkyl sulfides and contradict the recently reported c leavage of one of the alkyl sulfur bonds of sulfides upon adsorption.