title: Highly stable water-soluble platinum nanoparticles stabilized by hydrophilic N-heterocyclic carbenes.
abstract: Controlling the synthesis of stable metal nanoparticles in water is a current challenge in nanochemistry. The strategy presented herein uses sulfonated N-heterocyclic carbene (NHC) ligands to stabilize platinum nanoparticles (PtNPs) in water, under air, for an indefinite time period. The particles were prepared by thermal decomposition of a preformed molecular Pt complex containing the NHC ligand and were then purified by dialysis and characterized by TEM, high-resolution TEM, and spectroscopic techniques. Solid-state NMR studies showed coordination of the carbene ligands to the nanoparticle surface and allowed the determination of a (13)C-(195)Pt coupling constant for the first time in a nanosystem (940 Hz). Additionally, in one case a novel structure was formed in which platinum(II) NHC complexes form a second coordination sphere around the nanoparticle.
authors.affiliation: Departamento de Química Orgánica y Química Inorgánica, Universidad de Alcalá, Campus Universitario, 28871 Alcalá de Henares, Madrid (Spain).
authors.forename: Edwin A
authors.initials: EA
authors.lastname: Baquero
authors.forename: Simon
authors.initials: S
authors.lastname: Tricard
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Flores
authors.forename: Ernesto
authors.initials: E
authors.lastname: de Jesús
authors.forename: Bruno
authors.initials: B
authors.lastname: Chaudret
keywords: N-heterocyclic carbenes; nanoparticles; platinum; solid-state NMR spectroscopy; surface characterization