Rational Design of Transparent Nanowire Architectures with Tunable Geometries for Preventing Marine Fouling

Abstract

Marine biofouling is a sticky global problem that hinders maritime industries. Various microscale surface structures inspired by marine biological species have been explored for their anti‐fouling properties. However, systematic studies of anti‐marine‐fouling performance on surface architectures with characteristic length‐scales spanning from below 100 nm to greater than 10 µm are generally lacking. Herein, a study on the rational design and fabrication of ZnO/Al2O3 core–shell nanowire architectures with tunable geometries (length, spacing, and branching) and surface chemistry is presented. The ability of the nanowires to significantly delay or prevent marine biofouling is demonstrated. Compared to planar surfaces, hydrophilic nanowires can reduce fouling coverage by up to ≈60% after 20 days. The fouling reduction mechanism is mainly due to two geometric effects: reduced effective settlement area and mechanical cell penetration. Additionally, superhydrophobic nanowires can completely prevent marine biofouling for up to 22 days. The nanowire surfaces are transparent across the visible spectrum, making them applicable to windows and oceanographic sensors. Through the rational control of surface nano‐architectures, the coupled relationships between wettability, transparency, and anti‐biofouling performance are identified. It is envisioned that the insights gained from the work can be used to systematically design surfaces that reduce marine biofouling in various industrial settings.

Nanopatterning with Photonic Nanojets: Review and Perspectives in Biomedical Research

“…The wide range of compatible materials (polymers, glass, silicon) and morphological options (holes, pillars) that photonic nanojets enable offer remarkable chances to precisely engineer cell responses. These opportunities can be extended to other living organisms, such as bacteria [ 135 ], algae [ 136 ], and fungi [ 137 ], whose proliferation is of interest for several bio-applications, including the study and treatment of chronic bacterial infections.…”

Recent Developments of Superhydrophobic Surfaces (SHS) for Underwater Drag Reduction Opportunities and Challenges

“…This method can not only be carried out in plane, but also be applied to curved surface. Wang et al [152] found that the application of hydrophilic nanowires on microstructured surfaces can effectively reduce the coverage of marine organisms, which is the reason for the [150] Copyright 2018, Springer-Nature. b) The NW fabrication process is prepared.…”

“…Reproduced with permission. [152] Copyright 2020, Wiley-VCH. g) Magnified images of the nanorods of the prepared structures.…”

“…These NWs have similar inter-NW spacing as ≈0.05 µm. Reproduced with permission [152]. Copyright 2020, Wiley-VCH.…”

Assessing the impact of silicon nanowires on bacterial transformation and viability of Escherichia coli

“…4 This has led to many biomimicry studies, which attempt to replicate similar nanostructures using engineered materials, both for medical and nonmedical applications, such as marine anti-fouling coatings. 5 Surfaces covered in vertically-aligned nanometre-scale protrusions, such as black silicon, have been shown to exhibit similar antibacterial properties to the cicada wing. [6][7][8] The mechanisms driving this antimicrobial action remain an area of intense discussion in the literature.…”