Photoelectron Spectroscopy at Liquid Surfaces

Faubel, Manfred

doi:10.1142/9789812813473_0012

Cited by 57 publications

(110 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We use a fast flowing high-pressure liquid microjet in vacuum. The temperature as well as thermodynamic properties of the beam in vacuum can be characterized well, as has been shown by us and others [5]. The pumping conditions and the vacuum have to be arranged in such a way that the mean free path for photoelectrons in collisions with surrounding solvent molecules in the vicinity of the beam is minimized [7].…”

Section: Time-resolved Photoelectron Spectroscopy Near Liquid Interfacesmentioning

confidence: 82%

“…In addition to the element specificity, the technique can also provide information about an element's chemical environment or oxidation state. Due to the technical and conceptual problems with (volatile) liquids in vacuum, liquid phase (high pressure) ESCA is much less well established [3][4][5][6][7][8] than XPS at solid state surfaces. Only after Faubel et al developed the liquid beam technique in vacuum also volatile liquids like water could be investigated with photoelectron spectroscopy in vacuum [5][6][7][8].…”

Section: Esca and Photoelectron Spectroscopy Near Liquid Interfaces Xmentioning

confidence: 99%

“…Due to the technical and conceptual problems with (volatile) liquids in vacuum, liquid phase (high pressure) ESCA is much less well established [3][4][5][6][7][8] than XPS at solid state surfaces. Only after Faubel et al developed the liquid beam technique in vacuum also volatile liquids like water could be investigated with photoelectron spectroscopy in vacuum [5][6][7][8]. Since then, the chemical shift in the static ESCA approach has also been a particularly powerful observable for probing electron densities and molecular orbital energies in different liquid molecular environments [9,10].…”

Section: Esca and Photoelectron Spectroscopy Near Liquid Interfaces Xmentioning

confidence: 99%

“…6). The target is a liquid microjet, which was introduced by Faubel [5][6][7][8] some time ago (Fig. 4).…”

Section: Vacuum Chamber and Time-of-flight Photoelectron Spectrometermentioning

confidence: 99%

See 3 more Smart Citations

Ultrafast electronic spectroscopy for chemical analysis near liquid water interfaces: concepts and applications

et al. 2009

View full text Add to dashboard Cite

Electron spectroscopy for chemical analysis (ESCA) being conceptually a photoelectron spectroscopy is established as a chemically specific probe mostly for surface analysis. Liquid phase ESCA for volatile liquids has become possible through the development of the liquid microjet technique in vacuum enabling the measurement of liquid interface photoelectron emission at the high vapor pressure of volatile liquids. Recently we have been able to add the dimension of time to the liquid interface ESCA technique employing high-harmonics soft X-ray and UV/near IR femtosecond pulses in combination with liquid water micro beams in vacuum. The concepts as well as technical details are outlined and several characteristic applications are high-

show abstract

Section: Time-resolved Photoelectron Spectroscopy Near Liquid Interfacesmentioning

confidence: 82%

Section: Esca and Photoelectron Spectroscopy Near Liquid Interfaces Xmentioning

confidence: 99%

Section: Esca and Photoelectron Spectroscopy Near Liquid Interfaces Xmentioning

confidence: 99%

“…6). The target is a liquid microjet, which was introduced by Faubel [5][6][7][8] some time ago (Fig. 4).…”

Section: Vacuum Chamber and Time-of-flight Photoelectron Spectrometermentioning

confidence: 99%

See 2 more Smart Citations

Ultrafast electronic spectroscopy for chemical analysis near liquid water interfaces: concepts and applications

et al. 2009

View full text Add to dashboard Cite

show abstract

“…51 The 1b 1-liq is thus somewhat separated from the other signals and can be nicely followed in the pump-probe experiment. 69 In order to facilitate this, the time-resolved spectra have been plotted/color coded in a way that red displays a decrease and blue an increase of intensity, with respect to the reference spectrum at negative delays. Within the first 100 ps the intensity of the 1b 1-liq peak decreases, while the intensity of the corresponding 1b 1 gas phase signal increases.…”

Section: Resultsmentioning

confidence: 99%

Hydrogen bond dynamics of superheated water and methanol by ultrafast IR-pump and EUV-photoelectron probe spectroscopy

Vöhringer‐Martinez

Link

Lugovoy

et al. 2014

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Supercritical water and methanol have recently drawn much attention in the field of green chemistry. It is crucial to an understanding of supercritical solvents to know their dynamics and to what extent hydrogen (H) bonds persist in these fluids. Here, we show that with femtosecond infrared (IR) laser pulses water and methanol can be heated to temperatures near and above their critical temperature T c and their molecular dynamics can be studied via ultrafast photoelectron spectroscopy at liquid jet interfaces with high harmonics radiation. As opposed to previous studies, the main focus here is the comparison between the hydrogen bonded systems of methanol and water and their interpretation by theory. Superheated water initially forms a dense hot phase with spectral features resembling those of monomers in gas phase water. On longer timescales, this phase was found to build hot aggregates, whose size increases as a function of time. In contrast, methanol heated to temperatures near T c initially forms a broad distribution of aggregate sizes and some gas. These experimental features are also found and analyzed in extended molecular dynamics simulations. Additionally, the simulations enabled us to relate the origin of the different behavior of these two hydrogen-bonded liquids to the nature of the intermolecular potentials. The combined experimental and theoretical approach delivers new insights into both superheated phases and may contribute to understand their different chemical reactivities.

show abstract

Ambient Pressure Photoelectron Spectroscopy: Opportunities in Catalysis from Solids to Liquids and Introducing Time Resolution

2018

View full text Add to dashboard Cite

Photoelectron spectroscopy is an excellent technique to explore chemically complex systems in catalysis. However, due to a small mean free path of photoelectrons in gas, liquid, and solid media, the study of the gas–solid, liquid–gas, solid–liquid interfaces, as well as liquid homogeneous systems are a serious challenge. With differentially pumped analyzers this limitation ceases to exist and no longer restricts photoelectron spectroscopy only to ultra‐high vacuum conditions. Presently, photoemission studies at tens of mbar of pressure are possible. To reach atmospheric pressure and even higher, membrane‐covered closed cells have been developed. Graphene membranes are impermeable to molecules and almost transparent to photoelectrons. They are used as a pressure barrier between the enclosed cell at atmospheric pressure and the electron analyzer at vacuum while allowing transmission of photoelectrons. By accessing to atmospheric pressure range, with this kind of cell, photoemission studies will become a versatile in situ and operando tool for catalysis. Studies involving liquids in static conditions are an important aspect in this direction, which can be extended to homogeneous catalytic systems. Liquids are presently accessible using micro‐jets. Another aspect which is of paramount interest to investigate catalysts is time resolution. By improving the time resolution of photoemission measurements to the sub‐second regime it is possible to follow the kinetic changes that are crucial of a catalytic reaction, the changes that occur during catalyst pretreatment and activation, and notably to differentiate active species from spectator ones, which may be the dominating species in a classical experiment.

show abstract

Photoelectron Spectroscopy at Liquid Surfaces

Cited by 57 publications

References 16 publications

Ultrafast electronic spectroscopy for chemical analysis near liquid water interfaces: concepts and applications

Ultrafast electronic spectroscopy for chemical analysis near liquid water interfaces: concepts and applications

Hydrogen bond dynamics of superheated water and methanol by ultrafast IR-pump and EUV-photoelectron probe spectroscopy

Ambient Pressure Photoelectron Spectroscopy: Opportunities in Catalysis from Solids to Liquids and Introducing Time Resolution

Contact Info

Product

Resources

About