Facile Synthesis of Semiconductor and Noble Metal Nanocrystals in High-Boiling Two-Phase Liquid/Liquid Systems

Novel high-boiling liquid/liquid systems were introduced for the synthesis of semiconductor and noble metal nanocrystals. Polyols and long-chain hydrocarbons were utilized to form such two-phase systems. Because of the high-boiling nature, these systems may be conveniently employed for nanocrystal synthesis at relatively high temperatures (under the normal pressure) and thus are useful alternatives to toluene/water. CdS and Ag nanocrystals were successfully prepared in an octadecene (ODE)/glycerol system via interfacial processes, demonstrating the effectiveness of this class of two-phase systems. As-prepared nanocrystals had hydrophobic surfaces and were dispersed in the ODE phase of the system. Furthermore, a congeneric two-phase system of liquid paraffin/glycerol was also found to be effective for the synthesis of CdS and Ag nanocrystals.