Selective Synthesis of Gold Nanoparticles in Water/Alcohol Binary Solution Systems by Ultrasonic Irradiation

摘要

We have synthesized stable gold nanoparticles (AuNPs) by a simple ultrasonic irradiation in water/alcohol binary solutions without additive stabilizer agents. Methanol, ethanol, and 1-propanol are used as solvents. The morphology and optical properties of the sonochemically synthesized AuNPs are characterized using SEM and UV-vis spectroscopy. The average particle diameter of as-prepared AuNPs was 36 ± 10 nm for water/methanol system (methanol: 25 vol%), 56 ± 17 nm for water/ethanol system (ethanol: 35 vol%), and 24 ± 7 nm for water/1-propanol system (1-propanol: 35 vol%). The water/1-propanol system give the smallest average particle diameter together with the narrowest particle size distribution. This fact also support that the hydrophobicity of 1-propanol is higher, because the side chain of 1-propanol is longer than those in the other alcohols. Thus, it can be concluded that the dispersion of AuNPs is enhanced and their aggregation and growth are suppressed. [DOI: 10.1380/ejssnt.2015.427]