Electric fields control static charge during contact-friction-separation.

External electric fields can fully control and invert surface charge polarity and magnitude during contact electrification of polymer-polymer interfaces.

• Why it matters: Understanding the mechanisms behind contact electrification is crucial for managing issues in powder processing and optimizing energy harvesting devices like triboelectric nanogenerators.
• What they did: The study applied external electric fields to polymer contacts and used simulations to compare these fields to those generated by the flexoelectric effect, revealing a potential driving force.
• The result: Controlling electric fields enables direct manipulation of static charge, suggesting flexoelectric effects may significantly influence contact electrification processes.