Cracking the code of contact electrification: it's all about the touch!

Why do materials become charged when they touch? The phenomenon of contact electrification has puzzled scientists for centuries. Now, a collaborative study involving our researchers here at the Max Planck Institute for Polymer Research, along with colleagues at IST Austria, TU Wien, and the Centre for Electrochemistry and Surface Technology, Wiener Neustadt, has uncovered a surprising twist: the very act of contact shapes how materials charge!

Published in Nature, the research reveals that even identical materials spontaneously organize into a triboelectric series – a predictable ranking based on charge – simply through repeated contact. Our team's key contribution involved using surface-sensitive techniques to reveal subtle nanoscale morphological changes that occur during contact. We found that contacted surfaces become smoother at high spatial frequencies, suggesting a strong link between contact mechanics and charge transfer.

These findings challenge the traditional view of triboelectric series and open exciting new avenues for exploring mechanochemistry and flexoelectricity at the nanoscale. Read the full article in Nature to delve deeper into this fascinating discovery.