After functionalization, the G 0 films were prepared by redispersion of Geh in a water:isopropanol mixture (1:1 volume ratio) and submitted to bath ultrasound (300 W) for 30min. The resulting dispersion was centrifuged at 3000 RPM for 15min, followed by another centrifugation at 6000 RPM for 15min, to remove any aggregates that could disturb the film formation. The resulting supernatant is a very homogenous shiny black dispersion presenting a liquid crystal-like appearance.