14 DAY TRIAL // According to the conclusions of a new investigation, it would appear that the basic knowledge we thought we had on static electricity is wrong. The study found that the physical principles that underlie this phenomenon are more complex than originally thought.
Static electricity is one of the most commonly used ways of introducing electricity to students. Examples include balloons sticking to the ceilings, and tiny crackles that form on some bedsheets.
Children are taught that this type of electricity arises from electrons being transferred between different materials, such as for example between glass and wool, or balloons and cotton. Each substance and material has certain preferences when it comes to accumulating either positive or negative charges.
Until now, experts believed that statical electricity discharges did not transfer a lot of charge, but rather only limited amounts. The study indicates that most of these tenants are not correctly formulated.
The work demonstrates that electrical charges can form and be transferred between identical materials. When it comes to contact electrification, all materials have roughly the same behavior, the study also shows. Additionally, charges were found to be the product of chemical reactions.
Researchers also determined that each of the two surfaces becomes a “patchwork” of both positive and negative charges, which reach levels more than 1,000 times higher than the average charge that particular surface displays under normal conditions.
Details of how this works have been published in the June 25 issue of the top journal Science. The experts have determined that static electricity can also form when two pieces of an identical material lie flat against each other.
“According to the conventional view of contact electrification, this should not happen since the chemical potentials of the two surfaces/materials are identical and there is apparently no thermodynamic force to drive charge transfer,” the team explains, quoted by Wired.
For the new investigation, researchers were able to snap very high resolution charge readings, using a variant of atomic force microscopy called Kelvin force microscopy. The technique was developed specifically for conducting electricity-related investigations.
The microscope determined that each of the surfaces was covered with a patchwork of positive and negative charge areas, each of which was about 1 micrometer in diameter, and contained roughly 500 charged electrons.
In light of the new work, physics teams around the world will now focus their effort on understanding static electricity better, possibly providing the background for the introduction of new applications.