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Updated: Jun 25, 2025
Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica
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Partial Oxidation of Methanol on Gold: How Selectivity Is Steered by Low-Coordinated Sites
Salma Eltayeb1, Lenard L Carroll2, Lukas Dippel1
1Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany.
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.
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