title: Linear Tetraphenylmethane-Based Thioether Oligomers Stabilising an Entire Gold Nanoparticle by Enwrapping.
abstract: The design and synthesis of a novel linear thioether-based ligand subunit with a tetraphenylmethane core used in the stabilisation of gold nanoparticles (AuNPs) are presented. Mono-, tri, penta- and heptamers of the ligand have been synthesised and used to stabilise AuNPs by enwrapping. With the exception of the monomer, all ligands provide reliable long-term stability and redispersibility for the coated nanoparticles in common organic solvents. Despite variation of the oligomer length, all stable particles were of the same size within error tolerance (1.16±0.32 nm for the trimer, 1.15±0.30 nm for the pentamer, 1.17±0.34 nm for the heptamer), as investigated by transmission electron microscopy (TEM). These findings suggest that not only the number of sulfur atoms in the ligand, but also its bulkiness play a crucial role in stabilising the AuNPs. These findings are supported by thermogravimetric analysis (TGA), showing that AuNPs stabilised by the penta- or heptamer are passivated by a single ligand. Thermal stability measurements suggest a correlation between ligand coverage and thermal stability, further supporting these findings.
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland.
authors.forename: Mario
authors.initials: M
authors.lastname: Lehmann
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland.
authors.forename: Erich Henrik
authors.initials: EH
authors.lastname: Peters
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland. marcel.mayor@unibas.ch.|Institute for Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), P. O. Box 3640, 76021, Karlsruhe, Germany. marcel.mayor@unibas.ch.|Lehn Institute of Functional Materials (LIFM), Sun Yat-Sen University (SYSU), Guangzhou, P. R. China. marcel.mayor@unibas.ch.
authors.forename: Marcel
authors.initials: M
authors.lastname: Mayor
keywords: hybrid materials; ligand design; nanoparticles; oligomers; tetraphenylmethane