Monolayer to multilayer ultrathin films of the ionic liquid (IL) 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)amide have been prepared on Au(111) and Cu(100) surfaces using physical vapor deposition. The ion-surface interactions are studied using a combination of scanning tunnel microscopy, as well as ultraviolet and x-ray photoemission spectroscopies. It is found that the IL does not decompose at the surface of the metals, and that the IL interaction with the Cu(100) surface is much stronger than with the Au(111) surface. As a consequence, STM imaging at room temperature results in more stable imaging at the monolayer coverage on Cu(100) than on Au(111), and work function measurements indicate a large interface dipole upon deposition of a monolayer of IL on Cu. Additional IL depositions on the two surfaces result in two distinct behaviors for the IL core levels: a gradual energy shift of the core levels on Au and a set of two well defined monolayer and multilayer core level components found at fixed energies on Cu, due to the formation of a tightly bound monolayer. Finally, it is proposed that the particularly strong cation-Cu interaction leads to stabilization of the anion and prevents its decomposition at the surface of Cu(100).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.