Electrochemical prevention of marine biofouling with a carbon-chloroprene sheet

A carbon-chloroprene sheet (CCS) electrode was used for the electrochemical disinfection of the marine gram-negative bacterium Vibrio alginolyticus. When the electrode was incubated in seawater containing 10⁵ cells per ml for 90 min, the amount of adsorbed cells was 4.5 X 10³ cells per cm². When a potential of 1.2 V versus a saturated calomel electrode was applied to the CCS for 20 min, 67% of adsorbed cells were killed. This disinfection was due to the direct electrochemical oxidation of cells and not to a change in pH or to the generation of toxic substances, such as chlorine. In a 1-year field experiment, marine biofouling of a CCS-coated cooling pipe caused by attachment of bacteria and invertebrates was considerably reduced by application of a potential of 1.2 V versus a saturated calomel electrode. Since this method requires low potential electrical energy, use of a CCS coating appears to be a suitable method for the clean prevention of marine biofouling.