Mixed Ligand Shell Formation upon Catechol Ligand Adsorption on Hydrophobic TiO2 Nanoparticles
- Publikationstyp:
- Zeitschriftenaufsatz
- Metadaten:
-
- Autoren
- Eugen Schechtel
- Rene Doeren
- Hajo Frerichs
- Martin Panthoefer
- Mihail Mondeshki
- Wolfgang Tremel
- Autoren-URL
- https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=fis-test-1&SrcAuth=WosAPI&KeyUT=WOS:000487859300023&DestLinkType=FullRecord&DestApp=WOS_CPL
- DOI
- 10.1021/acs.langmuir.9b02496
- Externe Identifier
- Clarivate Analytics Document Solution ID: JA5BX
- PubMed Identifier: 31487189
- ISSN
- 0743-7463
- Ausgabe der Veröffentlichung
- 38
- Zeitschrift
- LANGMUIR
- Paginierung
- 12518 - 12531
- Datum der Veröffentlichung
- 2019
- Status
- Published
- Titel
- Mixed Ligand Shell Formation upon Catechol Ligand Adsorption on Hydrophobic TiO<sub>2</sub> Nanoparticles
- Sub types
- Article
- Ausgabe der Zeitschrift
- 35
Datenquelle: Web of Science (Lite)
- Andere Metadatenquellen:
-
- Autoren
- Eugen Schechtel
- René Dören
- Hajo Frerichs
- Martin Panthöfer
- Mihail Mondeshki
- Wolfgang Tremel
- DOI
- 10.1021/acs.langmuir.9b02496
- eISSN
- 1520-5827
- ISSN
- 0743-7463
- Ausgabe der Veröffentlichung
- 38
- Zeitschrift
- Langmuir
- Sprache
- en
- Online publication date
- 2019
- Paginierung
- 12518 - 12531
- Datum der Veröffentlichung
- 2019
- Status
- Published
- Herausgeber
- American Chemical Society (ACS)
- Herausgeber URL
- http://dx.doi.org/10.1021/acs.langmuir.9b02496
- Datum der Datenerfassung
- 2023
- Titel
- Mixed Ligand Shell Formation upon Catechol Ligand Adsorption on Hydrophobic TiO<sub>2</sub> Nanoparticles
- Ausgabe der Zeitschrift
- 35
Datenquelle: Crossref
- Abstract
- Modifying the surfaces of metal oxide nanoparticles (NPs) with monolayers of ligands provides a simple and direct method to generate multifunctional coatings by altering their surface properties. This works best if the composition of the monolayers can be controlled. Mussel-inspired, noninnocent catecholates stand out from other ligands like carboxylates and amines because they are redox-active and allow for highly efficient surface binding and enhanced electron transfer to the surface. However, a comprehensive understanding of their surface chemistry, including surface coverage and displacement of the native ligand, is still lacking. Here, we unravel the displacement of oleate (OA) ligands on hydrophobic, OA-stabilized TiO<sub>2</sub> NPs by catecholate ligands using a combination of one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy techniques. Conclusive pictures of the ligand shells before and after surface modification with catecholate were obtained by <sup>1</sup>H and <sup>13</sup>C NMR spectroscopy (the <sup>13</sup>C chemical shift being more sensitive and with a broader range). The data could be explained using a Langmuir-type approach. Gradual formation of a mixed ligand shell was observed, and the surface processes of catecholate adsorption and OA desorption were quantified. Contrary to the prevailing view, catecholate displaces only a minor fraction (∼20%) of the native OA ligand shell. At the same time, the total ligand density more than doubled from 2.3 nm<sup>-2</sup> at native oleate coverage to 4.8 nm<sup>-2</sup> at maximum catecholate loading. We conclude that the catecholate ligand adsorbs preferably to unoccupied Ti surface sites rather than replacing native OA ligands. This unexpected behavior, reminiscent of the Vroman effect for protein corona formation, appears to be a fundamental feature in the widely used surface modification of hydrophobic metal oxide NPs with catecholate ligands. Moreover, our findings show that ligand displacement on OA-capped TiO<sub>2</sub> NPs is not suited for a full ligand shell refunctionalization because it produces only mixed ligand shells. Therefore, our results contribute to a better understanding and performance of photocatalytic applications based on catecholate ligand-sensitized TiO<sub>2</sub> NPs.
- Addresses
- Institut für Anorganische Chemie und Analytische Chemie , Johannes Gutenberg-Universität Mainz , Duesbergweg 10-14 , D-55128 Mainz , Germany.
- Autoren
- Eugen Schechtel
- René Dören
- Hajo Frerichs
- Martin Panthöfer
- Mihail Mondeshki
- Wolfgang Tremel
- DOI
- 10.1021/acs.langmuir.9b02496
- eISSN
- 1520-5827
- Externe Identifier
- PubMed Identifier: 31487189
- Open access
- false
- ISSN
- 0743-7463
- Ausgabe der Veröffentlichung
- 38
- Zeitschrift
- Langmuir : the ACS journal of surfaces and colloids
- Sprache
- eng
- Medium
- Print-Electronic
- Online publication date
- 2019
- Paginierung
- 12518 - 12531
- Datum der Veröffentlichung
- 2019
- Status
- Published
- Datum der Datenerfassung
- 2019
- Titel
- Mixed Ligand Shell Formation upon Catechol Ligand Adsorption on Hydrophobic TiO<sub>2</sub> Nanoparticles.
- Sub types
- Research Support, Non-U.S. Gov't
- Journal Article
- Ausgabe der Zeitschrift
- 35
Datenquelle: Europe PubMed Central
- Abstract
- Modifying the surfaces of metal oxide nanoparticles (NPs) with monolayers of ligands provides a simple and direct method to generate multifunctional coatings by altering their surface properties. This works best if the composition of the monolayers can be controlled. Mussel-inspired, noninnocent catecholates stand out from other ligands like carboxylates and amines because they are redox-active and allow for highly efficient surface binding and enhanced electron transfer to the surface. However, a comprehensive understanding of their surface chemistry, including surface coverage and displacement of the native ligand, is still lacking. Here, we unravel the displacement of oleate (OA) ligands on hydrophobic, OA-stabilized TiO2 NPs by catecholate ligands using a combination of one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy techniques. Conclusive pictures of the ligand shells before and after surface modification with catecholate were obtained by 1H and 13C NMR spectroscopy (the 13C chemical shift being more sensitive and with a broader range). The data could be explained using a Langmuir-type approach. Gradual formation of a mixed ligand shell was observed, and the surface processes of catecholate adsorption and OA desorption were quantified. Contrary to the prevailing view, catecholate displaces only a minor fraction (∼20%) of the native OA ligand shell. At the same time, the total ligand density more than doubled from 2.3 nm-2 at native oleate coverage to 4.8 nm-2 at maximum catecholate loading. We conclude that the catecholate ligand adsorbs preferably to unoccupied Ti surface sites rather than replacing native OA ligands. This unexpected behavior, reminiscent of the Vroman effect for protein corona formation, appears to be a fundamental feature in the widely used surface modification of hydrophobic metal oxide NPs with catecholate ligands. Moreover, our findings show that ligand displacement on OA-capped TiO2 NPs is not suited for a full ligand shell refunctionalization because it produces only mixed ligand shells. Therefore, our results contribute to a better understanding and performance of photocatalytic applications based on catecholate ligand-sensitized TiO2 NPs.
- Autoren
- Eugen Schechtel
- René Dören
- Hajo Frerichs
- Martin Panthöfer
- Mihail Mondeshki
- Wolfgang Tremel
- Autoren-URL
- https://www.ncbi.nlm.nih.gov/pubmed/31487189
- DOI
- 10.1021/acs.langmuir.9b02496
- eISSN
- 1520-5827
- Ausgabe der Veröffentlichung
- 38
- Zeitschrift
- Langmuir
- Sprache
- eng
- Country
- United States
- Paginierung
- 12518 - 12531
- Datum der Veröffentlichung
- 2019
- Status
- Published
- Datum, an dem der Datensatz öffentlich gemacht wurde
- 2020
- Titel
- Mixed Ligand Shell Formation upon Catechol Ligand Adsorption on Hydrophobic TiO2 Nanoparticles.
- Sub types
- Journal Article
- Research Support, Non-U.S. Gov't
- Ausgabe der Zeitschrift
- 35
Datenquelle: PubMed
- Beziehungen:
- Eigentum von