Insect wings possess unique, multifaceted properties that have drawn increasing attention in recent times. They serve as an inspiration for engineering of materials with exquisite properties. The structure–function relationships of insect wings are yet to be documented in detail. In this review, we present a detailed understanding of the multifunctional properties of insect wings, including micro- and nanoscale architecture, material properties, aerodynamics, sensory perception, wettability, optics, and antibacterial activity, as investigated by biologists, physicists, and engineers. Several established modeling strategies and fabrication methods are reviewed to engender novel ideas for biomimetics in diverse areas.

Modeling and simulation of bacteria-nanostructure interactions can reveal critical insights underlying the physics of the process, verify and predict bacterial behaviour, or optimize bactericidal activity.

Bioinspired nanostructured antibacterial surfaces are among the most promising recent discoveries in nanotechnology to tackle microbial colonization of surfaces, especially with the growing challenge of antimicrobial resistance. Reactive ion etching (RIE) is one of the few nanofabrication techniques that has been demonstrated to be capable of generating biomimetic nanostructures on large substrates through a combination of physical and chemical etching. However, the physics behind the formation of these structures and their spatiotemporal evolution is poorly understood, primarily limited by the challenges associated with placing in situ characterization instruments inside the process chamber. The limited understanding in the field leads to poor reproducibility, constraining the widespread acceptance and application of this technique. This work describes maskless RIE of commercially pure titanium substrates using chlorine and fluorine plasma. It is demonstrated that the chamber condition plays a critical role toward determining the morphology of the nanostructures generated, and high aspect ratio (HAR) nanostructures can be generated reproducibly by following proper cleaning protocols involving fluorine plasma by scavenging the SiOCl species that accumulate in the chamber walls over time. Furthermore, the control of several process parameters to reproducibly fabricate various types of nanostructures such as nanoridges, nanopillars, and nanowires are demonstrated, along with insights into the underlying physical principles. HAR nanopillars are generated, and their bactericidal mechanism and efficiency are shown to be primarily dependent on their aspect ratio. This study provides insights to resolve the hitherto poorly understood events of fabrication of bioinspired nanostructures by RIE with important implications for reliably and reproducibly engineering biomaterial surfaces with bactericidal activity.

Radiofrequency (RF) shielding is a type of electromagnetic (EM) shielding that prevents RF EM radiation from entering a building. Electrostatic fields, radio waves, and medical equipment can be insulated by multifunctional composites consisting of unique core–shell heterostructures; such materials are in high demand, given the rapid improvements in medical electronics and their expanding clinical applications, which represent a serious challenge of EM pollution in clinical settings. In order to avoid malfunction, the electronics in critical care devices in hospitals must be shielded from radiation. In order to create a material that can block radio waves while still utilizing RF to disinfect the surface, we built core–shell nanostructures to encase critical medical electronics. In this work, we discuss a polymer composite that is customized to provide EM shielding while also safeguarding critical care bioelectronics. Its bactericidal function, on the other hand, prevents nosocomial dangerous microorganisms from spreading contamination. We developed a library of Fe3O4@Ag and Ag@Fe3O4 core–shell and binary heterostructures with configurable Ag or Fe3O4 shell thicknesses. These heterostructures were subsequently combined with ethylene–vinyl acetate (EVA), a thermoplastic polymer, to create flexible composites that may attenuate incident EM radiation. The protective viability (SE) of Fe3O4@Ag core–shell and Ag@Fe3O4 binary nanoparticles in EVA was −32.1 and −20 dB, respectively. Due to localized heating, the Fe3O4@Ag- and Ag@Fe3O4-based nanocomposites exhibited “self-cleaning” behavior, displaying antibacterial activity in the vicinity of a 2.4 GHz wireless fidelity source against Pseudomonas aeruginosa. Taken together, these multifunctional, adaptable composites can protect electronic gadgets from EM radiation and harness RF to render the surface antibacterial, an important attribute in clinical settings.

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