Sonochemistry and sonoluminescence in aqueous AuCl4- solutions in the presence of surface-active solutes

Abstract

The 515 kHz ultrasound-initiated reduction of AuCl4- to Au(0) was examined as a function of the concentration of various surface-active solutes. The amount of AuCl4- reduced in the presence of ethanol, propan-1-ol, and butan-1-ol was found to be dependent on the surface excess of the alcohol at the gas/solution interface, i.e., the relative concentration of the alcohol at the gas/solution interface compared to the bulk solution concentration. The efficiency of reduction of AuCl4- in the presence of the surfactants sodium dodecyl sulfate or octaethylene glycol monodecyl ether was found to be related to the monomer concentration of the surfactant in solution. The light emitted (sonoluminescenc..