Perfect Composition Depth Profiling of Ionic Liquid Surfaces Using High-Resolution RBS/ERDA.

0463598 - ÚCHP 2017 RIV JP eng J - Journal Article
Nakajima, K. - Zolboo, E. - Ohashi, T. - Lísal, Martin - Kimura, K.
Perfect Composition Depth Profiling of Ionic Liquid Surfaces Using High-Resolution RBS/ERDA.
Analytical Sciences. Roč. 32, č. 10 (2016), s. 1089-1094. ISSN 0910-6340. E-ISSN 1348-2246
R&D Projects: GA ČR(CZ) GA16-12291S
Institutional support: RVO:67985858
Keywords : surface structure * ionic liquid * hydrogen
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 1.228, year: 2016

In order to reveal the surface structures of large molecular ionic liquids (ILs), the near-surface elemental depth distributions of 1-alkyl 3-methylimidazolium bis(trifluoromethanesulfonyl)imide
([CnC1Im][Tf2N], n = 2, 6, 10) were studied using high-resolution Rutherford backscattering spectroscopy (HRBS) in combination with high-resolution elastic recoil detection analysis (HR-ERDA).
The elemental depth profiles of all constituent elements, including hydrogen, were derived from HR-ERDA/HRBS measurements, so that the profiles would reproduce both HR-ERDA and HRBS
spectra simultaneously. The derived elemental depth profiles agree with state-of-the-art molecular dynamics simulations, indicating the feasibility of this method. A controversy concerning the preferential orientation of [C2C1Im] at the surface has been resolved by this new combination analysis; namely, the [C2C1Im] cation has a preferential orientation with the ethyl chain pointing to wards the vacuum in the topmost molecular layer.
Permanent Link: http://hdl.handle.net/11104/0264574