Sonochemical synthesis of ruthenium nanoparticles

Ruthenium nanoparticles have been prepared by sonochemical reduction of a ruthenium chloride solution using ultrasound frequencies in the range 20-1056 kHz. The reduction was monitored by UV-Vis absorption spectrophotometry. Reduction proceeds sequentially from Ru(III) to Ru(II) to Ru(0) and takes almost 13 h. The Ru particles produced by the ultrasound reduction have diameters between 10 and 20 nm as measured by transmission electron microscope image.