Synergistic enhancement of microbubble formation in ultrasound irradiated H2O–CH3OH mixtures probed by dynamic light scattering

Abstract

This report investigates the formation of microbubbles in water–methanol mixtures upon ultrasound irradiation and its correlation with the yield of H₂ obtained as a result of sonochemical splitting of water. The yield of hydrogen produced by sonochemical reaction is monitored at different compositions of water–methanol mixtures. The evidence for the formation of microbubbles upon ultrasound irradiation is obtained by the dynamic light scattering technique. Microbubble formation during ultrasound irradiation of water–methanol mixtures, their stability and size distribution, has been quantitatively estimated. The effect of composition of the water–methanol mixture and duration of irradiation on the extent of bubble formation has been inferred from the changes in the light scattering intensity and its time correlation function. Exceptional stability of microbubbles without any additives is observed at a certain composition of the water–methanol mixture (4 : 3, v/v). The extent of microbubbles formed in the mixture correlates well with the yield of hydrogen detected.