Here, we show that the coating remains highly hydrophilic and antimicrobial after long term leaching in water , and after many repeated bacterial inoculations. However, the silver exchanged zeolite A coating showed considerable degradation in mildly acidic and basic solutions. The acid/base stability issues are resolved by using zeolite A/ZSM-5 hybrid coating. In order to achieve all desired properties, we prepared a coating that consisted of zeolite A seeds imbedded within a ZSM-5 matrix. ZSM-5 is a high silica zeolite which can be produced by an in-situ crystallization process using TPAOH as a template. ZSM-5 shows superior acid/base resistance, as well as corrosion resistance , and acts to protect the zeolite A imbedded within the coating while the zeolite A seeds provided the hydrophilic and antimicrobial function. Data was obtained for hybrid coatings formed on top of a ZSM-5 pure phase membrane, as well as for hybrid coatings formed directly on the substrate using a template free ZSM-5 synthesis solution. All coatings were shown to be highly hydrophilic and antimicrobial after silver exchange.
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