Polydicyanamide film near rubber sealing. Optical microscopy image, picture width 200 micrometers, brightfield contrast mode. It was prepared by electropolymerizing of dicyanamide-based ionic liquid during testing high voltage graphene capacitor technology (<a rel="nofollow" class="external free" href="https://doi.org/10.1016/j.jpowsour.2015.01.153">https://doi.org/10.1016/j.jpowsour.2015.01.153</a>).
<a href="//commons.wikimedia.org/wiki/User:Tavoromann" title="User:Tavoromann">Tavo Romann</a>
CC BY 4.0
<span class="int-own-work" lang="en">Own work</span>