Negative Charging of Au Nanoparticles during Methanol Synthesis from CO 2 /H 2 on a Au/ZnO Catalyst: Insights from Operando IR and Near‐Ambient‐Pressure XPS and XAS Measurements

Autor: Alexander Yu. Klyushin, Robert Schlögl, Ali M. Abdel-Mageed, Axel Knop-Gericke, Azita Rezvani, R. Jürgen Behm
Rok vydání: 2019
Předmět:
Zdroj: Angewandte Chemie International Edition. 58:10325-10329
ISSN: 1521-3773
1433-7851
DOI: 10.1002/anie.201900150
Popis: The electronic and structural properties of Au/ZnO under industrial and idealized methanol synthesis conditions have been investigated. This was achieved by kinetic measurements in combination with time-resolved operando infrared (DRIFTS) as well as in situ near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) and X-ray absorption near-edge spectroscopy (XANES) measurements at the O K-edge together with high-resolution electron microscopy. The adsorption of CO during the reaction revealed the presence of negatively charged Au nanoparticles/Au sites during the initial phase of the reaction. Near-ambient-pressure XPS and XANES demonstrate the build-up of O vacancies during the reaction, which goes along with a substantial increase in the rate of methanol formation. The results are discussed in comparison with previous findings for Cu/ZnO and Au/ZnO catalysts.
Databáze: OpenAIRE