Superhydrophobic 304 Stainless Steel Mesh for the Removal of High-Density Polyethylene Microplastics

Abstract

Microplastics are a global issue that affects the environment, economy, as well as human health. Herein, we present a superhydrophobic 304 stainless steel mesh obtained by chemical etching followed by a liquid-phase deposition of lauric acid that can be used for microplastic removal. Field emission scanning electron microscopy (FE-SEM) and high-resolution X-ray photoelectron spectroscopy (HR-XPS), among other techniques, were used to identify the hierarchical structure and chemical composition of the surface. They revealed that iron laurate decreased the surface free energy. The 304 stainless steel mesh was superhydrophobic (169°) and superoleophilic (0°). Taking advantage of these wetting properties, we showed an innovative use of these superhydrophobic surfaces in the removal of microplastics. Additionally, we analyzed the removal efficiency from a surface and colloidal point of view that allowed us to explain and clarify why microplastics can also be removed by their wetting properties. The loss of a double electrostatic cloud between the microplastics and the predominance of van der Waals interactions in the organic phase promote the removal of these persistent pollutants from water.

Revealing the Mechanism of Ink Flaking from Surfaces of Palm Leaves (Corypha umbraculifera)

“…We then evaluated the spreading of different plant oils on palm leaves, such as castor oil, peanut oil, clove oil, and camphor oil (Figure S3a,b). All of these oils displayed a smaller contact angle than the modern commercial ink, and camphor oil can even achieve a superoleophilic effect on palm leaves (<5°) . The polar and dispersive components of these oils were also determined by the OWRK method (Figure S3c and Table S2).…”

“…All of these oils displayed a smaller contact angle than the modern commercial ink, and camphor oil can even achieve a superoleophilic effect on palm leaves (<5°). 33 The polar and dispersive components of these oils were also determined by the OWRK method (Figure S3c and Table S2). It is disclosed that the higher ratio of the dispersive component facilitates spreading on the surface.…”

Biomimetic Superhydrophobic Materials for Environmental Applications

“…It is explained that the repellent cloud that forms on the surface of the microplastic in water enhances dispersion. Yet, in the organic phase, van der Waals interactions cause microplastic to aggregate [40].…”

Soft and Rigid Integrated Durable Coating for Large-Scale Deicing

“…A superhydrophobic surface (SHS) was developed by the combination of the micro/nanostructure and low surface energy. − Lim et al reported a well-textured superhydrophobic surface, which exhibited a low ice adhesion strength of ∼10 kPa . It should be noted that SHS can also be used for oil–water separation, microplastics removal, and anti-corrosion . Recently, a slippery liquid-infused porous surface (SLIPS) has been discovered and received wide attention for anti-icing application.…”

“…The ice accretion on surfaces may bring negative influence and even endanger human lives in a range of areas (e.g., power transmission lines and airplanes). − Thus, there is an increasing urgent need for the easy removal of ice. Compared with active strategies (e. g., electrical heating , and photothermal strategies , ), passive strategies such as coatings have the advantages of simplicity, cost efficiency, and no energy demand.…”