Credit: Image courtesy of University of California, Berkeley and Lawrence Berkeley National Laboratory reprinted from ACS Nano.
When graphene is supported by an electrical insulator, negatively charged molecules are attracted to each other and form islands. The microscopy image shows one such island. Theory predicted that as the island unexpectedly forms, additional electrons from graphene flow into the island and keep the molecules together. These additional electrons make the island a more stable structure compared to one where the molecules stay apart. Scientists could use the islands to modify the graphene for electronic applications.