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Updated: Jun 16, 2025
Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method
Published on: June 14, 2019
Light-induced manipulation of ultra-low surface tension droplets on stable quasi-liquid surfaces
Shouzheng Jiao1, Peng Cheng1, Qian Li2
1State Key Laboratory of Urban Water Resource & Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.
Hypothesis:
Perfluorocarbon is commonly used as a coolant, chemical reaction carrier solvent, medical anti-hypoxic agents and blood substitutes. The realization of non-contact complex manipulation of perfluorocarbon liquids is urgently needed in human life and industrial production. However, most liquid-repellent interfaces are ineffective for the transport of ultra-low surface tension perfluorocarbon liquids, and struggle to maintain good durability due to unstable air or oil cushions in the surface. Therefore, preparing surfaces for stable non-contact complex manipulation of ultra-low surface tension droplets remains a challenge.
Experiments:
In this paper, a novel solution, a photothermal responsive droplet manipulation surface based on polydimethylsiloxane brushes, has been reported. On this surface, droplets with different surface tensions (as low as 10 mN/m) can be efficiently manipulated through induced near-infrared light. Notably, this surface maintains its effectiveness after exposure to extreme anthropogenic conditions.
Findings:
The interface effect between perfluorocarbon droplets and polydimethylsiloxane brushes by near-infrared light-induced was investigated in detail. In addition, ultra-low surface tension droplets demonstrate the ability to transport solid particles. The conductive droplets exhibit sophisticated manipulation realizing the controlled switching of smart circuits. This research opens up new possibilities for advancing the capabilities and adaptability of ultralow surface tension droplets in a range of applications.
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