Laser induced graphene coatings with antimicrobial properties have been developed that protect feedspacers in membrane filtration modules from microbial fouling. Because the coating material is electrically conductive, electrical currents can be applied to enhance the antifouling efficiency.
Laser-induced graphene (LIG) is a conductive carbon material that can be generated on surfaces of many types of polymers using a common laser. The process is low cost because it consumes only a minimum amount of electrical energy and is very environmentally friendly compared to other methods to generate graphene nanomaterials as it works without solvents or acids and does not produce waste. Moreover it is very sustainable since recycled polymers can be used.
This LIG material was incorporated into a coating paste/paint, which can be commercialized. To demonstrate the applicability of the coating material, a polymer mesh that is commonly used as a spacer component in a membrane filtration module was coated with the laser-induced graphene coating. This LIG spacer was incorporated into a membrane filtration module and showed reduced microbial growth on both the spacer and the adjacent membrane. The innovative nature of this product includes the creation of an electrically conductive spacer, whose electrification further enhances the antibacterial and antifouling effect. This technology might be used in water filtration or purification technologies to reduce the risk of plant contamination and ensure the production of (drinking) water with low microbial load.