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Charge-Promoted Self-Metalation of Porphyrins on an Oxide Surface.

ABSTRACT: Metalation and self-metalation reactions of porphyrins on oxide surfaces have recently gained interest. The mechanism of porphyrin self-metalation on oxides is, however, far from being understood. Herein, we show by a combination of results obtained with scanning tunneling microscopy, photoemission spectroscopy, and DFT computations, that the self-metalation of 2H-tetraphenylporphyrin on the surface of ultrathin MgO(001) films is promoted by charge transfer. By tuning the work function of the MgO(001)/Ag(001) substrate, we are able to control the charge and the metalation state of the porphyrin molecules on the surface.

SUBMITTER: Egger L

PROVIDER: S-EPMC7986846 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Charge-Promoted Self-Metalation of Porphyrins on an Oxide Surface.

Egger Larissa L Hollerer Michael M Kern Christian S CS Herrmann Hannes H Hurdax Philipp P Haags Anja A Yang Xiaosheng X Gottwald Alexander A Richter Mathias M Soubatch Serguei S Tautz F Stefan FS Koller Georg G Puschnig Peter P Ramsey Michael G MG Sterrer Martin M

Angewandte Chemie (International ed. in English) 20210114 10

Metalation and self-metalation reactions of porphyrins on oxide surfaces have recently gained interest. The mechanism of porphyrin self-metalation on oxides is, however, far from being understood. Herein, we show by a combination of results obtained with scanning tunneling microscopy, photoemission spectroscopy, and DFT computations, that the self-metalation of 2H-tetraphenylporphyrin on the surface of ultrathin MgO(001) films is promoted by charge transfer. By tuning the work function of the Mg ...[more]

PMID: 33245197

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