title: Controlled UV-C light-induced fusion of thiol-passivated gold nanoparticles.
abstract: Thiol-passivated gold nanoparticles (AuNPs) of a relatively small size, either decorated with chromophoric groups, such as a phthalimide (Au@PH) and benzophenone (Au@BP), or capped with octadecanethiol (Au@ODCN) have been synthesized and characterized by NMR and UV-vis spectroscopy as well as transmission electron microscopy (TEM). These NPs were irradiated in chloroform at different UV-wavelengths using either a nanosecond laser (266 and 355 nm, ca. 12 mJ/pulse, 10 ns pulse) or conventional lamps (300 nm < λ < 400 nm and ca. 240 nm < λ < 280 nm) and the new AuNPs were characterized by X-ray and UV-vis spectroscopy, as well as by TEM. Laser irradiation at 355 nm led to NP aggregation and precipitation, while the NPs were photostable under UV-A lamp illumination. Remarkably, laser excitation at 266 nm induced a fast (minutes time-scale) increase in the size of the NPs, producing huge spherical nanocrystals, while lamp-irradiation at UV-C wavelengths brought about nanonetworks of partially fused NPs with a larger diameter than the native NPs.
authors.affiliation: Molecular Science Institute (ICMOL), Universidad de Valencia, 46980 Paterna, Valencia, Spain.
authors.forename: Salvador
authors.initials: S
authors.lastname: Pocoví-Martínez
authors.forename: Miriam
authors.initials: M
authors.lastname: Parreño-Romero
authors.forename: Said
authors.initials: S
authors.lastname: Agouram
authors.forename: Julia
authors.initials: J
authors.lastname: Pérez-Prieto