Reactivity of Carbon Dioxide on Nickel: Role of CO in the Competing Interplay between Oxygen and Graphene.
The catalytic conversion of carbon dioxide to synthetic fuels and other valuable chemicals is an issue of global environmental and economic impact. In this report we show by means of X-ray photoelectron spectroscopy in the millibar range that, on a Ni surface, the reduction of carbon dioxide is indirectly governed by the CO chemistry. While the growth of graphene and the carbide-graphene conversion can be controlled by selecting the reaction temperature, oxygen is mainly removed by CO, since oxygen reduction by hydrogen is a slow process on Ni. Even though there is still a consistent pressure gap with respect to industrial reaction conditions, the observed phenomena provide a plausible interpretation of the behavior of Ni/Cu based catalysts for CO2 conversion and account for a possible role of CO in the methanol synthesis process.
†Physics Department, University of Trieste, via Valerio 2, I-34127 Trieste, Italy.
Enrico
E
Monachino
‡Abteilung Anorganische Chemie, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
Mark
M
Greiner
‡Abteilung Anorganische Chemie, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
Axel
A
Knop-Gericke
‡Abteilung Anorganische Chemie, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
Robert
R
Schlögl
§Physics Department and CENMAT, University of Trieste, via Valerio 2, I-34127 Trieste, Italy.|∥IOM-CNR Laboratorio TASC, Area Science Park, S.S. 14 km 163.5, I-34149 Basovizza, Trieste, Italy.
Carlo
C
Dri
§Physics Department and CENMAT, University of Trieste, via Valerio 2, I-34127 Trieste, Italy.|∥IOM-CNR Laboratorio TASC, Area Science Park, S.S. 14 km 163.5, I-34149 Basovizza, Trieste, Italy.
Erik
E
Vesselli
§Physics Department and CENMAT, University of Trieste, via Valerio 2, I-34127 Trieste, Italy.|∥IOM-CNR Laboratorio TASC, Area Science Park, S.S. 14 km 163.5, I-34149 Basovizza, Trieste, Italy.
Giovanni
G
Comelli
carbon dioxide; carbon monoxide; graphene; hydrogen; nickel; reduction