Here, by creating different types of artificial barrier layer against bacterial attachment, anti-biofouling properties were endowed on three metallic surfaces - aluminum, stainless steel and titanium. To each metallic surface, a tailored chemical oxidation process was applied to grow scalable oxide structures with an additional appropriate coating, resulting in three different types of anti-biofouling barrier, a thin water film, an air layer and an oil layer. Fluorescence images of the attached bacteria showed that the water layer improved the anti-biofouling performance up to 8-12 h and the air layer up to 12-24 h, comparable with the lifetime of the air layer. In comparison, the oil layer exhibited the best anti-biofouling performance by suppressing the fouled area by < 10% up to 72 h regardless of the substratum type. The present work provides simple, low-cost, scalable strategies to enhance the anti-biofouling performance of industrially important metallic surfaces. [Formula: see text].
Keywords: Anti-biofouling; artificial barrier layer; industrial metal; wettability.