Science
Sliding water droplets can generate electrical charge and corrode metal
New research shows that rain running down smooth surfaces before hitting coated metals can create electric fields strong enough to damage the material.
The short version
- A study published in Nature reveals that water droplets sliding down smooth surfaces like windows or leaves acquire a positive electrical charge.
- When these charged droplets hit a coated metal plate, they generate a strong electric field that can burrow through protective coatings and corrode the metal underneath.
- The discovery could help explain why industrial anti-corrosion coatings sometimes fail, offering new insights into a major infrastructure challenge.
Key facts
- The study, led by physicist Hans-Jürgen Butt of the Max Planck Institute for Polymer Research, found that sliding water droplets become electrified, whereas water dropped directly onto surfaces does not.[Scientific American]
- In experiments, water droplets sliding down surfaces and onto a Teflon-coated copper plate burrowed through the Teflon to create pits in the copper.[Scientific American]
- Researchers believe the sliding water carries a positive charge that interacts with the negatively charged metal, creating an electric field that ultimately degrades the metal.[Scientific American]
- The findings are not considered a danger to humans, and attempts to harness rainwater at a large scale to generate electricity remain unfeasible.[Scientific American]
Sources
- Electric rain can eat through metalScientific American metered