We report a novel passive microfluidic mixer design for mixing enhancement based on dynamic disturbances due to bubble generation produced by catalytic decomposition of hydrogen peroxide. A Y-shaped passive microfluidic mixer with a width and depth of and , respectively, with platinum deposition on the partial undersurface of the mixing channel for catalytic decomposition, is demonstrated. Various Reynolds numbers (0.06 to 63.5) and concentrations are tested to investigate their effects on the mixing. The experimental results show that mixing can be significantly improved either with the decrease of volumetric flow rate at a given concentration or with the increase of concentration at intermediate Reynolds numbers based on the present design. The mixing index scatters between 0.8 and 1.0 at for all concentrations if in the mixing channel. However, the concentration has no significant effect on mixing provided . In addition, the maximum mixing enhancement for , 10, 100, and (, 0.63, 6.35, and 63.5) at are 5.7, 11.85, 6.27, and 4.8, respectively, with in this study.