title: Mechanistic Insights into the Formation of Dodecanethiolate-Stabilized Magnetic Iridium Nanoparticles: Thiosulfate vs Thiol Ligands.
abstract: The synthesis of stable and isolable iridium nanoparticles with an average core size of ∼1.2 ± 0.3 nm was achieved by employing sodiumS-dodecylthiosulfate as a ligand precursor during the modified Brust-Schiffrin reaction. Transmission electron microscopy (TEM) of the isolated Ir nanoparticles revealed a high degree of monodispersity. Further characterizations with1H NMR, FT-IR, UV-vis spectroscopy, thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS) confirmed that the synthesized Ir nanoparticles are stabilized by dodecanethiolate ligands produced upon the adsorption/cleavage ofS-dodecylthiosulfate on the growing Ir nanoparticle surface. By comparison, synthetic attempts employing dodecanethiol as a stabilizing ligand led to the formation of Ir-thiolate species (Ir(SR)3) as an intermediate and Ir-hydroxide species at the completion of reaction. Mechanistic investigations of these two reactions usingS-dodecylthiosulfate and dodecanethiol provided deeper understandings on the novelty of thiosulfate ligands, which allow the successful formation of stable thiolate-capped Ir nanoparticles. Moreover, these Ir nanoparticles were shown to have strong magnetic properties.
authors.affiliation: Department of Chemistry and Biochemistry, and Department of Physics and Astronomy, California State University, Long Beach , 1250 Bellflower Boulevard, Long Beach, California 90840-9507, United States.
authors.forename: Diego J
authors.initials: DJ
authors.lastname: Gavia
authors.affiliation: Department of Chemistry and Biochemistry, and Department of Physics and Astronomy, California State University, Long Beach , 1250 Bellflower Boulevard, Long Beach, California 90840-9507, United States.
authors.forename: Yeonjin
authors.initials: Y
authors.lastname: Do
authors.affiliation: Department of Chemistry and Biochemistry, and Department of Physics and Astronomy, California State University, Long Beach , 1250 Bellflower Boulevard, Long Beach, California 90840-9507, United States.
authors.forename: Jiyeong
authors.initials: J
authors.lastname: Gu
authors.affiliation: Department of Chemistry and Biochemistry, and Department of Physics and Astronomy, California State University, Long Beach , 1250 Bellflower Boulevard, Long Beach, California 90840-9507, United States.
authors.forename: Young-Seok
authors.initials: YS
authors.lastname: Shon