Sonochemiluminescence in an aqueous solution of Ru(bpy)3Cl2.

The sonochemiluminescence spectra of electron-excited ions *[Ru(bpy)3]2+ was registered for the first time during sonolysis of argon saturated aqueous solutions of Ru(bpy)3Cl2 with low concentration. At single-bubble sonolysis, the luminescence band of ruthenium is recorded at a concentration of Ru(bpy)3Cl2 from 10-6 M, and at multibubble from 10-5 M. Possible mechanisms for the appearance of the band of a tris-bipyridyl ruthenium(II) complex on the background of an structureless continuum of water in the spectra of sonoluminescence are analyzed. Based on the results of the comparison of the sonoluminescence spectra of Ru(bpy)3Cl2 aqueous solutions with the sonoluminescence spectra of aqueous solutions of rhodamine B (which has a high quantum yield of photoluminescence) it was established that a possible mechanism of sonophotoluminescence does not play a decisive role in ruthenium sonoluminescence. The effect of radical acceptors (O2, C2H5OH, Cd2+, I-) on ruthenium sonoluminescence is analyzed. The most significant mechanism for the formation of electron-excited ions *[Ru(bpy)3]2+ during sonolysis is the sonochemiluminescence in oxidation-reduction reactions involving [Ru(bpy)3]2+ ions and radical products of sonolysis of water (OH, H, e-aq) in the solution volume.