Superhydrophilic–superhydrophobic patterned surfaces on glass substrate for water harvesting

Abstract

Directional water harvesting is a special ability of flora and fauna in nature. Wettability-patterned surfaces inspired by natural structures have been extensively researched, and could be a great potential avenue for easing water shortage. However, preparation strategies for these nature-inspired cases, including UV irradiation with mask technology, femtosecond laser direct writing and chemical treatment are time-consuming, cost-ineffective and environmentally unfriendly. In this paper, robust and durable superhydrophobic (SHB) glass substrate was prepared by using laser-induced backward transfer (LIBT) technique and fluoroalkylsilane (FAS) modification. Then wedge-shaped superhydrophilic (SHL) patterns on the SHB surfaces were rapidly constructed by inexpensive and commercially available fiber laser ablation for fog harvesting. This facile, cost effective, and non-corrosive preparation method described herein could be an alternative way to construct SHL-SHB patterns on glass substrate, which could be used for microfluidic devices, droplet manipulation and cell screening.

Surface Engineering of Ceramic Nanomaterials for Separation of Oil/Water Mixtures

“…There are other examples where this combination of properties has been used to engineer materials for oil/water separation (Zhu et al, 2017 ; Ge et al, 2019 , 2020a ). A variety of nanomaterials have been used to create meshes (Jiang et al, 2017 ; Zhang et al, 2018a , 2019 ; Nanda et al, 2019 ; Wang et al, 2019 ; Gong et al, 2020 ), membranes (Attia et al, 2018 ; Huang et al, 2018 ; Ma et al, 2018 ; Qing et al, 2018 ; Zhao et al, 2018 ; Subramanian et al, 2019 ; Cheng et al, 2020 ), sponges (Huang et al, 2019b ; Li et al, 2019b ), and fabrics (Cheng et al, 2018 ; Chauhan et al, 2019 ; Lin et al, 2019 ; Zhou et al, 2019 ; Dan et al, 2020 ) with superhydrophobic and superoleophilic properties for oil/water separation (Ferrero et al, 2019 ; Zulfiqar et al, 2019 ; Latthe et al, 2020 ; Lin et al, 2020 ; Topuz et al, 2020 ; Zhang et al, 2020b ). Most of these materials separate oil either by filtration, absorption, or both.…”

Preparation of Robust Superhydrophobic Sand by Chemical Vapor Deposition of Polydimethylsiloxane for Oil/Water Separation

“…On the other hand, different kinds of the substrate can be utilized to fabricate superhydrophobic materials such as sawdust, [ 29 ] cotton, [ 30 ] copper mesh, [ 31 ] sponge, [ 23 ] stainless steel mesh, [ 32 ] sand, [ 3,33–35 ] glass, [ 36 ] and so forth. Generally, sand is an ideal inorganic material due to its low cost, ecofriendly, high chemical stability, and abundance in the desert and seacoast.…”

High‐speed wire electrical discharge machining to create superhydrophobic surfaces for magnesium alloys with high corrosion and wear resistance

“…Superhydrophobicity is a highly sought‐after property not only because it imparts good corrosion resistance and wear resistance to materials, but also because it allows for unique applications of materials, such as antibacterial, [ 14 ] oil/water separation, [ 15 ] drag reduction, [ 16 ] self‐cleaning, [ 17 ] anti‐icing, [ 18 ] anticorrosion [ 19 ] and water harvesting. [ 20 ] Generally, the successful preparation of superhydrophobic surfaces requires two essential features: ordered micro‐/nanostructures and low surface energy. Superhydrophobic surfaces have been successfully prepared on magnesium alloys by numerous methods, such as laser ablation, sol–gel, hydrothermal, electrophoretic deposition and chemical vapour deposition.…”