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Dynamic Equilibrium at the HCOOH-Saturated TiO₂(110)-Water Interface.

ABSTRACT: Carboxylic acids bind to titanium dioxide (TiO₂) dissociatively, forming surface superstructures that give rise to a (2 × 1) pattern detected by low-energy electron diffraction. Exposing this system to water, however, leads to a loss of the highly ordered surface structure. The formate-covered surface was investigated by a combination of diffraction and spectroscopy techniques, together with static and dynamic ab initio simulations, with the conclusion that a dynamic equilibrium exists between adsorbed formic acid and water molecules. This equilibrium process is an important factor for obtaining a better understanding of controlling the self-cleaning properties of TiO₂, because the formic acid monolayer is responsible for the amphiphilic character of the surface.

SUBMITTER: Brandalise Nunes F

PROVIDER: S-EPMC10084457 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Dynamic Equilibrium at the HCOOH-Saturated TiO2(110)-Water Interface.

Brandalise Nunes Fernanda F Comini Nicolò N Diulus J Trey JT Huthwelker Thomas T Iannuzzi Marcella M Osterwalder Jürg J Novotny Zbynek Z

The journal of physical chemistry letters 20230323 13

Carboxylic acids bind to titanium dioxide (TiO2) dissociatively, forming surface superstructures that give rise to a (2 × 1) pattern detected by low-energy electron diffraction. Exposing this system to water, however, leads to a loss of the highly ordered surface structure. The formate-covered surface was investigated by a combination of diffraction and spectroscopy techniques, together with static and dynamic ab initio simulations, with the conclusion that a dynamic equilibrium exist ...[more]

PMID: 36952665

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