Polydopamine exhibits high potential as coating of materials used for medical devices, antifouling, and corrosion prevention. Repetitive cyclic voltammetry on gold electrodes was used to deposit polydopamine by anodic oxidation. Investigation of polydopamine formation in the pH range 5–8 showed that coating at pH 6.5 permits selective polydopamine formation on the electrode, while auto-oxidation of dopamine in the electrolyte could be suppressed. The optimized conditions then were transferred to stainless steel electrodes. At pH 6.5–6.6, an anodic peak current density of 12.9 μA/mm2 was measured using a plane stainless steel anode in 5 mM dopamine solution. During experimental scale-up, anodic coating of 1.4622 steel plates in galvanostatic experiments led to formation of a colored polydopamine surface, which exhibited reduction of the water contact angle by 13.5°. The controlled anodic polydopamine formation is of a particular value for an economic polydopamine coating of the conductive material in larger-scale applications.

This paper presents the current state of development and selected technological challenges in the application of ecologically and economically sustainable nets for aquaculture based on ongoing development projects. These aim at the development of a new material system of high-strength stainless steel wires as net material with environmentally compatible antifouling properties for nearshore and offshore aquacultures. Current plastic netting materials will be replaced with high-strength stainless steel to provide a more environmentally friendly system that can withstand more severe mechanical stresses (waves, storms, tides and predators). A new antifouling strategy is expected to solve current challenges, such as ecological damage (e.g., due to pollution from copper-containing antifouling substances or microplastics), high maintenance costs (e.g., cleaning and repairs), and shorter service life. Approaches for the next development steps are presented based on previous experience as well as calculation models based on this experience.