SEP 01, 2020

No Child's Play - Advanced Bubble Manipulation Method can Transform Chemical Processing

WRITTEN BY: Daniel Duan

Gas bubbles are fascinating, playful objects in children's eyes. In fact, they play an essential role in many industrial processes, such as hydrogen fuel production and sewage water treatment. The current practices of manipulating bubbles underwater are inefficient because they depend on the hydrophobic surface where the bubbles were spawned, and the speed of movement is often slow and passive, relying heavily on the buoyancy of bubbles. 

According to a recent report, a team of Chinese researchers has devised an innovative method that allows them to guide the swift movement of bubbles with an external magnetic field. The scientists first generated pointy microstructures on a surface by vaporizing the material with a precise laser. Then they infuse the surface with ferrofluid, a colloid made of billions of tiny ferromagnetic particles. 

The finished FLAMS, or ferrofluid-infused laser-ablated microstructured surfaces, pulled off some unusual feats. Using a guiding magnet, the researchers managed to accelerate a typical size air bubble to an ultrafast velocity over 25 mm/s (1 inch/s) without popping on a leveled FLAMS. They also dragged bubbles downward against buoyancy and moved heavy objects (up to 500 times their own mass) between the bubbles' air-water interface. 

The authors hoped that their high-performance bubble manipulation technique finds potential applications in water decontamination, electrochemistry, and other areas that depend on gas evolution.

This latest research is published in the journal Nano Letters.

Source: C&EN via Youtube