Phase transfer of noble metal nanoparticles to organic solvents

Nanoparticles are finding increasing application because of their unusual optical properties. Processing these materials would be drastically simplified if they could be routinely dispersed into a wide variety of polar and nonpolar solvents. We report the synthesis of a new bidentate thiol ligand, (Z)-octadec-9-en-1-yl-5-(1,2-dithiolan-3-yl)pentanoate, and demonstrate its ability to phase transfer gold nanospheres (5-70 nm), nanorods, and silver nanoparticles efficiently from water into various organic solvents. The protocol obviates the need for solid-phase steps or polymeric ligands. Electronic spectra and electron micrographs demonstrate that the particles are fully dispersed in a variety of organic solvents after transfer.