title: The Origin of the Catalytic Activity of a Metal Hydride in CO2 Reduction.
abstract: Atomic hydrogen on the surface of a metal with high hydrogen solubility is of particular interest for the hydrogenation of carbon dioxide. In a mixture of hydrogen and carbon dioxide, methane was markedly formed on the metal hydride ZrCoHx in the course of the hydrogen desorption and not on the pristine intermetallic. The surface analysis was performed by means of time-of-flight secondary ion mass spectroscopy and near-ambient pressure X-ray photoelectron spectroscopy, for the in situ analysis. The aim was to elucidate the origin of the catalytic activity of the metal hydride. Since at the initial stage the dissociation of impinging hydrogen molecules is hindered by a high activation barrier of the oxidised surface, the atomic hydrogen flux from the metal hydride is crucial for the reduction of carbon dioxide and surface oxides at interfacial sites.
authors.affiliation: École Polytechnique Fédérale de Lausanne (EPFL), 1951, Sion, Switzerland. shunsuke.kato@epfl.ch.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kato
authors.affiliation: Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600, Dübendorf, Switzerland.
authors.forename: Santhosh Kumar
authors.initials: SK
authors.lastname: Matam
authors.affiliation: Max-Planck-Institut für Eisenforschung GmbH, 40237, Düsseldorf, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Kerger
authors.affiliation: Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600, Dübendorf, Switzerland.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Bernard
authors.affiliation: Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600, Dübendorf, Switzerland.
authors.forename: Corsin
authors.initials: C
authors.lastname: Battaglia
authors.affiliation: Max-Planck-Institut für Eisenforschung GmbH, 40237, Düsseldorf, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Vogel
authors.affiliation: Max-Planck-Institut für Eisenforschung GmbH, 40237, Düsseldorf, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Rohwerder
authors.affiliation: École Polytechnique Fédérale de Lausanne (EPFL), 1951, Sion, Switzerland. andreas.zuettel@epfl.ch.
authors.forename: Andreas
authors.initials: A
authors.lastname: Züttel
keywords: CO2 reduction; heterogeneous catalysis; hydrocarbons; hydrogen; hydrogenation