Self-metalation of monophosphonic acid tetraphenylporphyrin on TiO2(110)-(1×1)

Fernández CC, Wechsler D, Lytken O, Steinrück HP, Williams FJ (2022)

Publication Type: Journal article

Publication year: 2022

Journal

Surface Science Elsevier

Book Volume: 717

Article Number: 122005

DOI: 10.1016/j.susc.2021.122005

Abstract

Fundamental studies on the interaction of porphyrin molecules with oxide surfaces are important due to the relevance of these systems in emerging technologies. In this work, we used X-ray photoelectron spectroscopy (XPS) to study the interaction of solution-deposited monophosphonic acid tetraphenylporphyrin (MPTPP) molecules with well-defined rutile TiO2(110)-(1×1) surfaces as a function of coverage and temperature. We found that molecules adsorb mainly in their free-base form with some molecules protonating on the surface at room temperature. In agreement with the behavior of carboxylic acid functionalized porphyrin molecules, raising the temperature results in porphyrin self-metalation and the temperature onset for self-metalation shifts to higher values as the coverage is increased. Furthermore, we found that self-metalation is accompanied by surface reduction, and we propose a mechanism based on the formation of oxygen vacancies driven by water desorption. Our findings contribute towards the understanding of the rich surface chemistry that porphyrin molecules have on oxide surfaces.

Authors with CRIS profile

Daniel Wechsler Lehrstuhl für Physikalische Chemie II Ole Lytken Lehrstuhl für Physikalische Chemie II Hans-Peter Steinrück Lehrstuhl für Physikalische Chemie II

Involved external institutions

Universidad de Buenos Aires (UBA) / University of Buenos Aires AR Argentina (AR)

How to cite

APA:

Fernández, C.C., Wechsler, D., Lytken, O., Steinrück, H.-P., & Williams, F.J. (2022). Self-metalation of monophosphonic acid tetraphenylporphyrin on TiO2(110)-(1×1). Surface Science, 717. https://dx.doi.org/10.1016/j.susc.2021.122005

MLA:

Fernández, Cynthia C., et al. "Self-metalation of monophosphonic acid tetraphenylporphyrin on TiO2(110)-(1×1)." Surface Science 717 (2022).

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