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Interfacial electric fields catalyze Ullmann coupling reactions on gold surfaces.

ABSTRACT: The electric fields created at solid-liquid interfaces are important in heterogeneous catalysis. Here we describe the Ullmann coupling of aryl iodides on rough gold surfaces, which we monitor in situ using the scanning tunneling microscope-based break junction (STM-BJ) and ex situ using mass spectrometry and fluorescence spectroscopy. We find that this Ullmann coupling reaction occurs only on rough gold surfaces in polar solvents, the latter of which implicates interfacial electric fields. These experimental observations are supported by density functional theory calculations that elucidate the roles of surface roughness and local electric fields on the reaction. More broadly, this touchstone study offers a facile method to access and probe in real time an increasingly prominent yet incompletely understood mode of catalysis.

SUBMITTER: Stone IB

PROVIDER: S-EPMC9491086 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Interfacial electric fields catalyze Ullmann coupling reactions on gold surfaces.

Stone Ilana B IB Starr Rachel L RL Hoffmann Norah N Wang Xiao X Evans Austin M AM Nuckolls Colin C Lambert Tristan H TH Steigerwald Michael L ML Berkelbach Timothy C TC Roy Xavier X Venkataraman Latha L

Chemical science 20220901 36

The electric fields created at solid-liquid interfaces are important in heterogeneous catalysis. Here we describe the Ullmann coupling of aryl iodides on rough gold surfaces, which we monitor <i>in situ</i> using the scanning tunneling microscope-based break junction (STM-BJ) and <i>ex situ</i> using mass spectrometry and fluorescence spectroscopy. We find that this Ullmann coupling reaction occurs only on rough gold surfaces in polar solvents, the latter of which implicates interfacial electric ...[more]

PMID: 36320717

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