An oil spill cleanup system has a vessel, a separator within the vessel for separating oil and water, a pump for pumping an oilwater mixture into the separator, and one or more probes and submersibles having hoses connected to the pump, for collecting the oilwater mixture. The graphene-containing layer includes an activated surface which is hydrophilic. The method further includes stacking the upper metal plate on the lower metal plate, before drying the respective composite material layers, and integrally bonding the second composite material layer and the third composite material layer to form a single intermediate composite material layer.