Title: Partial Oxidation of Methanol on Gold: How Selectivity Is Steered by Low-Coordinated Sites
Authors: Salma Eltayeb, Lenard L. Carroll, Lukas Dippel, Mersad Mostaghimi, Wiebke Riedel, Lyudmila V. Moskaleva, and Thomas Risse
DOI: https://doi.org/10.1021/acscatal.3c04578
Date: 05/23/2024
Working Group: WG3
Grant Period: 2nd GP 2023-2024
Grant Period Goal (number): [GAPG-1] Dissemination. [GAPG-5] Control and manipulation at the nanoscale
Deliverables: 3.1.1
Countries involved: Germany, South Africa
Number of female/young/ITC coauthors: 3/4/0
Abstract: Partial methanol oxidation proceeds with high selectivity to methyl formate (MeFo) on nanoporous gold (npAu) catalysts. As low-coordinated sites on npAu were suggested to affect the selectivity, we experimentally investigated their role in the isothermal selectivity for flat Au(111) and stepped Au(332) model surfaces using a molecular beam approach under well-defined conditions. Direct comparison shows that steps enhance desired MeFo formation and lower undesired overoxidation. DFT calculations reveal differences in oxygen distribution that enhance the barriers to overoxidation at steps. Thus, these results provide an atomic-level understanding of factors controlling the complex reaction network on gold catalysts, such as npAu.
