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Northwestern research team turns theory of static electricity on its head


Bartosz Grzybowski, a physical chemist at Northwestern University, and his team of colleagues offer evidence in a paper published in Science, that shows that what scientists have believed to be true about the causes behind the creation of static electricity, is wrong. Instead of one object winding up with more or less electrons as a result of rubbing together, they claim, there is an actual transfer of slight amounts of actual material.


More information: The Mosaic of Surface Charge in Contact Electrification, Science, Published Online 23 June 2011. DOI:10.1126/science.1201512


ABSTRACT

When dielectric materials are brought into contact and then separated, they develop static electricity. For centuries, it has been assumed that such contact charging derives from the spatially homogeneous material properties (along the material's surface) and that within a given pair of materials, one charges uniformly positively and the other negatively. We demonstrate that this picture of contact charging is incorrect. While each contact-electrified piece develops a net charge of either positive or negative polarity, each surface supports a random “mosaic” of oppositely charged regions of nanoscopic dimensions. These mosaics of surface charge have the same topological characteristics for different types of electrified dielectrics and accommodate significantly more charge per unit area than previously thought.


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Lees verder: http://www.physorg.com/news/2011-06-northw...lectricity.html


Bron: PhysOrg