A combined droplet train and ambient pressure photoemission spectrometer for the investigation of liquid/vapor interfaces [electronic resource].
- Published:
- Berkeley, Calif. : Lawrence Berkeley National Laboratory, 2008.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy. - Additional Creators:
- Lawrence Berkeley National Laboratory
United States. Department of Energy. Office of Scientific and Technical Information - Access Online:
- www.osti.gov
- Summary:
- We describe a combined ambient pressure photoelectron spectroscopy/droplet train apparatus for investigating the nature and heterogeneous chemistry of liquid/vapor interfaces. In this instrument a liquid droplet train with typical droplet diameters from 50...150 {micro}m is produced by a vibrating orifice aerosol generator (VOAG). The droplets are irradiated by soft X-rays (100...1500 eV) in front of the entrance aperture of a differentially pumped electrostatic lens system that transfers the emitted electrons into a conventional hemispherical electron analyzer. The photoemission experiments are performed at background pressures of up to several Torr, which allows the study of environmentally important liquid/vapor interfaces, in particular aqueous solutions, under equilibrium conditions. The exposure time of the droplet surface to the background gases prior to the XPS measurement can be varied, which will allow future kinetic measurements of gas uptake on liquid surfaces. As an example, a measurement of the surface composition of a χ = 0.21 aqueous methanol solution is presented. The concentration of methanol at the vapor/liquid interface is enhanced by a factor of about 3 over the bulk value, while the expected bulk value is recovered at depths larger than about 1.5 nm.
- Note:
- Published through SciTech Connect.
05/01/2008.
"lbnl-998e"
Physical Chemistry Chemical Physics 10 21 ISSN 1463-9076 FT
Wilson, Kevin R.; Worsnop, Douglas R.; Bluhm, Hendrik; Starr, David E.; Wong, Ed K.
Chemical Sciences Division - Funding Information:
- DE-AC02-05CH11231
View MARC record | catkey: 14130941