skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Local Environment and Interactions of Liquid and Solid Interfaces Revealed by Spectral Line Shape of Surface Selective Nonlinear Vibrational Probe

Abstract

Vibrational spectral lineshape contains important detailed information of molecular vibration and reports its specific interactions and couplings to its local environment. In this work, recently developed sub-1 cm-1 high-resolution broadband sum frequency generation vibrational spectroscopy (HR-BB-SFG-VS) was used to measure the -C≡N stretch vibration in the 4-n-octyl-4’-cyanobiphenyl (8CB) Langmuir or Langmuir-Blodgett (LB) monolayer as a unique vibrational probe, and the spectral lineshape analysis revealed the local environment and interactions at the air/water, air/glass, air/calcium fluoride and air/-quartz interfaces for the first time. The 8CB Langmuir or LB film is uniform and the vibrational spectral lineshape of its -C≡N group has been well characterized, making it a good choice as the surface vibrational probe. Lineshape analysis of the 8CB -C≡N stretch SFG vibrational spectra suggests the coherent vibrational dynamics and the structural and dynamic inhomogeneity of the -C≡N group at each interface are uniquely different. In addition, it is also found that there are significantly different roles for water molecules in the LB films on different substrate surfaces. These results demonstrated the novel capabilities of the surface nonlinear spectroscopy in characterization and in understanding the specific structures and chemical interactions at the liquid and solid interfaces in general.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1339819
Report Number(s):
PNNL-SA-120513
Journal ID: ISSN 1932-7447
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry. C; Journal Volume: 120; Journal Issue: 44
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Chen, Shun-Li, Fu, Li, Chase, Zizwe A., Gan, Wei, and Wang, Hong-Fei. Local Environment and Interactions of Liquid and Solid Interfaces Revealed by Spectral Line Shape of Surface Selective Nonlinear Vibrational Probe. United States: N. p., 2016. Web. doi:10.1021/acs.jpcc.6b10215.
Chen, Shun-Li, Fu, Li, Chase, Zizwe A., Gan, Wei, & Wang, Hong-Fei. Local Environment and Interactions of Liquid and Solid Interfaces Revealed by Spectral Line Shape of Surface Selective Nonlinear Vibrational Probe. United States. doi:10.1021/acs.jpcc.6b10215.
Chen, Shun-Li, Fu, Li, Chase, Zizwe A., Gan, Wei, and Wang, Hong-Fei. 2016. "Local Environment and Interactions of Liquid and Solid Interfaces Revealed by Spectral Line Shape of Surface Selective Nonlinear Vibrational Probe". United States. doi:10.1021/acs.jpcc.6b10215.
@article{osti_1339819,
title = {Local Environment and Interactions of Liquid and Solid Interfaces Revealed by Spectral Line Shape of Surface Selective Nonlinear Vibrational Probe},
author = {Chen, Shun-Li and Fu, Li and Chase, Zizwe A. and Gan, Wei and Wang, Hong-Fei},
abstractNote = {Vibrational spectral lineshape contains important detailed information of molecular vibration and reports its specific interactions and couplings to its local environment. In this work, recently developed sub-1 cm-1 high-resolution broadband sum frequency generation vibrational spectroscopy (HR-BB-SFG-VS) was used to measure the -C≡N stretch vibration in the 4-n-octyl-4’-cyanobiphenyl (8CB) Langmuir or Langmuir-Blodgett (LB) monolayer as a unique vibrational probe, and the spectral lineshape analysis revealed the local environment and interactions at the air/water, air/glass, air/calcium fluoride and air/-quartz interfaces for the first time. The 8CB Langmuir or LB film is uniform and the vibrational spectral lineshape of its -C≡N group has been well characterized, making it a good choice as the surface vibrational probe. Lineshape analysis of the 8CB -C≡N stretch SFG vibrational spectra suggests the coherent vibrational dynamics and the structural and dynamic inhomogeneity of the -C≡N group at each interface are uniquely different. In addition, it is also found that there are significantly different roles for water molecules in the LB films on different substrate surfaces. These results demonstrated the novel capabilities of the surface nonlinear spectroscopy in characterization and in understanding the specific structures and chemical interactions at the liquid and solid interfaces in general.},
doi = {10.1021/acs.jpcc.6b10215},
journal = {Journal of Physical Chemistry. C},
number = 44,
volume = 120,
place = {United States},
year = 2016,
month =
}
  • Vibrational sum-frequency generation spectroscopy (SFG) is used for in situ probing of molecular vibrations at interfaces associated with solid-electrolyte interphases (SEI) in systems relevant to lithium-ion batteries. SFG is interface-selective and can suppress nonresonant signals from metal electrodes. Two interfaces were observed: the electrode-SEI interface and the electrolyte-SEI interface. The SEI was formed on Au or Cu by potential cycling from 2.0 V–0.2 V (vs. Li/Li +) in ethylene carbonate (EC) and LiClO₄ in tetrahydrofuran (THF). Li deposition occurs on Au but not on Cu. SFG of the electrolyte-SEI interface with Cu shows EC transitions whose intensities oscillate during potentialmore » cycling. The smaller oscillations are attributed to EC potential-dependent reorientation; the larger to an optical interference effect associated with the SEI layer thickness. The larger EC interference oscillations seen on Cu are absent on Au because the SEI on Au is thicker and more opaque. Lithium ethylene dicarbonate (LiEDC) and possibly ethylene oxide are observed at the electrode-SEI interface. This interfacial structure varies little after the first cycle of SEI formation. THF is also observed at the electrode interface with a degree of mobility that increases during the first few four potential cycles and then levels off.« less
  • Transitions to unoccupied Si(111) 2 x 1 surface states have been observed at the silicon 1s absorption edge. The surface features are distinguished from bulk absorption by taking the difference between the absorption measured by monitoring the surface-sensitive LVV Auger decay (88 eV kinetic energy) and the bulk-sensitive KLL Auger decay (1610 eV kinetic energy). The difference curve reveals a surface peak which is centered 0.3 +- 0.15 eV above the conduction-band minimum and which disappears upon exposure of the clean surface to atomic hydrogen. By tuning the photon energy to the energy of this surface peak and selectively excitingmore » the surface, we have extracted the contribution of the 2 x 1 surface to the total Si L/sub 2,3/VV Auger line shape. We find that the surface contribution to the Si L/sub 2,3/VV Auger line shape lies 0.5 +- 0.1 eV kinetic energy above the total contribution due to the presence of the Si(111) 2 x 1 occupied dangling-bond surface states, and the intensity of the bulk plasmon loss at 70 eV kinetic energy is suppressed due to the presence of the 2 x 1 ..pi..-bonded surface. Formation of the Si(111)-(1 x 1)H surface produces changes in the Auger spectra which are consistent with the removal of the occupied dangling-bond surface states from the band gap, the introduction of a Si-H bonding level 6.5 eV below the valence-band maximum, and the enhancement of the bulk-plasmon loss. We also find that the intensity of the high-energy Auger satellite at 103 eV kinetic energy is sensitive to the excitation photon energy within the vicinity of the silicon K edge and present a viable mechanism which accounts for this phenomenon.« less
  • The combination band of the C-O and the Ru-CO stretch vibrational modes of CO adsorbed on Ru(001) has been used to study vibrational dispersion effects by infrared absorption spectroscopy. For an ordered CO layer both vibrational modes can be excited far from the {Gamma} point while fulfilling the {bold q}{approx}0 condition through {bold q} vector matching. It is found that diluted layers lacking intermolecular interactions display a symmetrical and narrow line shape which broadens substantially for the ({radical}(3){times}{radical}(3))R30{degree}CO layer and displays a pronounced asymmetry, in good agreement with theory. {copyright} {ital 1997} {ital The American Physical Society}
  • Moessbauer spectroscopy has been applied for studying the local environment of {sup 57}Fe probe atoms within iron-doped CaMn{sub 7}O{sub 12} manganite with a perovskite-like structure. The {sup 57}Fe spectra recorded in the paramagnetic temperature range 90 K<T<380 K, where CaMn{sub 7}O{sub 12} has a rhombohedral structure (R3), were discussed supposing Fe{sup 3+} probe cations to replace manganese in the octahedral (Mn{sup 3+}O{sub 6}) and (Mn{sup 4+}O{sub 6}) polyhedra. A very small (<3%) part of Fe{sup 3+} probe cations characterized by very large quadrupole splitting ({approx}2 mm/s) suggests that a few amounts of {sup 57}Fe probe can be substituted for Mn{supmore » 3+} in the (9e) positions with approximately a square planar surrounding. In the temperature range 380 K<T<450 K, the {sup 57}Fe Moessbauer spectra undergo a sharp change which can be due to a formation (at T{sub CO}{approx}380 K) and a gradual growth with temperature of the cubic manganite phase (Im3). At T{>=}450 K, the {sup 57}Fe spectrum reveals single Fe{sup 3+} sites in an oxygen symmetric octahedral surrounding. This can be well explained by a fast electron exchange Mn{sup 3+}{r_reversible}Mn{sup 4+}, leading to the crystallographic equivalence of all MnO{sub 6} positions. At the temperature range T<T{sub M2} (=90 K), an appearance of the distributions of the hyperfine magnetic field values at the {sup 57}Fe nucleus up to {approx}350 kOe (at 77.4 K) was observed. This result is an independent experimental evidence of magnetic ordering in the manganese sublattice.« less