Femtosecond laser bionic fabrication of slippery lubricant-infused hierarchical surface for marine antifouling

Marine biofouling presents a formidable challenge to the structure integrity and operation longevity of marine vessels, subsea engineering equipment and underwater exploratory systems. In response to this challenge, the bionic slippery lubricant-infused surfaces or coatings have emerged as a highly promising frontier for marine antifouling engineering. Consequently, in this paper, femtosecond laser quasi-athermal processing is employed to low-surface-energy PDMS elastomers, creating high-quality hierarchical micro/nanostructures with a near-superhydrophobicity (148.3 ± 0.8°) including microgrooves, micropillars, microprotrusions, nanopores and nanoparticles. Simultaneously, the trans-scale formation mechanism of this hierarchical micro/nanostructure is revealed in depth. Subsequent lubricant infusion yields slippery surfaces with ultra-low water sliding angle of 6.7 ± 1.4° that effectively suppress marine biofilm adhesion under static and dynamic conditions. Systematical characterizations and assessments demonstrate a pronounced synergistic effect between high-aspect-ratio laser-induced micro/nanostructures and silicone oil. However, the long-term stability and service-stage evolution of lubricant-infused surfaces under marine fouling conditions remain insufficiently understood. For this, the stability tests of lubricant layer coupled with shear simulation conditions reveal a three-stage evolution law of lubricant-infused surfaces in simulated marine service environment, viz. full oil-infused, low oil-depleted and conformal oil-coated stages. These findings not only advance femtosecond laser trans-scale micro/nanofabrication for functional surface/interfaces engineering, but also provide a solid experimental and technology basis for developing next-generation long-term, high-performance and environment-friendly lubricant-infused surfaces. Graphical