Towards energy efficient nanobubble generation with fluidic oscillation

Nanobubbles are a mystery as to their stability and longevity. So far their uses are limited to high value applications, such as medical imaging and controlled drug delivery and release. The current methods of nanobubble generation and understanding of nanobubble interfacial structure are reviewed. The analysis of the potential benefits of nanobubbles leads to the conclusion that if energy efficient nanobubbles that were flexible in injection and production were available, there would be widespread usage. The hypothesis that a recent methodology for energy efficient microbubble generation could be extended to nanobubble generation is presented and reviewed. The current applications and promising potential applications for energy efficient microbubbles are discussed, ranging from bioreactors to dispersal of ozone, through flotation separations and enhanced chemical reactions by reactive separation.

Graphical AbstractFluidic oscillation with a microporous (or nanoporous) diffuser system produces bubble clouds on the size of the pore, so far down to the 20 m scale. The mechanism is energy efficient, since in any injection system, gas must be blown into the liquid. Interpret the graphic as “fluidic oscillator” + “microporous diffuser” = “microbubbles on the size of the pore.”Figure optionsDownload full-size imageDownload high-quality image (2648 K)Download as PowerPoint slideResearch Highlights► Nanobubble longevity: [1] showed hydrogen bonds that reduce the gas diffusivity. ► Stabilization: [20] MD simulations show hydrophobic interactions on the interface. ► Nanobubbles are vectors for genetic material. [7] ultrasound. [8] plasmonics. ► Three new mechanisms for microbubble generation. [25] electrohydrodynamics. ► [26] stirring electric field effect. [29] energy efficiency with fluidic oscillation.