title: The solvation of electrons by an atmospheric-pressure plasma.
abstract: Solvated electrons are typically generated by radiolysis or photoionization of solutes. While plasmas containing free electrons have been brought into contact with liquids in studies dating back centuries, there has been little evidence that electrons are solvated by this approach. Here we report direct measurements of solvated electrons generated by an atmospheric-pressure plasma in contact with the surface of an aqueous solution. The electrons are measured by their optical absorbance using a total internal reflection geometry. The measured absorption spectrum is unexpectedly blue shifted, which is potentially due to the intense electric field in the interfacial Debye layer. We estimate an average penetration depth of 2.5 ± 1.0 nm, indicating that the electrons fully solvate before reacting through second-order recombination. Reactions with various electron scavengers including H(+), NO2(-), NO3(-) and H2O2 show that the kinetics are similar, but not identical, to those for solvated electrons formed in bulk water by radiolysis.
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Rumbach
authors.affiliation: Department of Chemistry and Biochemistry, Notre Dame Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana, 46556, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Bartels
authors.affiliation: Department of Chemical and Biomolecular Engineering, Case Western Reserve University, Cleveland, Ohio, 44106, USA.
authors.forename: R Mohan
authors.initials: RM
authors.lastname: Sankaran
authors.affiliation: 1] Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA [2] Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: David B
authors.identifier: 0000000189481442
authors.initials: DB
authors.lastname: Go