Facile preparation of superhydrophobic metal foam for durable and high efficient continuous oil-water separation

Abstract

Foam-based material with unique wettability is one of the promising materials for developing oil-spill cleanup, benefiting from its intrinsic interconnected three-dimensional skeleton, oil permeation and water repellency. However, obtaining a foam-based material capable of in situ separating oil spills, especially with superhydrophobic durability and simple recycling mode, remains challenging. Herein, we reported a one-step spraying approach to fabricate fluorinated ethylene propylene (FEP)/ polyvinylidene fluoride (PVDF)/ ultrafine polyurethane (UPU)/ hydrophobic nanosilica (HSiO 2)-decorated nickel foam coating with a static water contact angle (WCA) of 157±1.5˚ and a static oil contact angle (OCA) of 0˚. Owing to the foldability of the coated nickel foam, we established a continuous in-situ collection apparatus by external pumping on 3D nickel foam box. UPU addition endowed the resultant 3D nickel foam with excellent interfacial adhesion. After 7 days of continuous oil-water experiment that simulated cleanup oil-spill, the static WCA of the 3D nickel foam with 10 wt% UPU was still above 130˚. Notablely, after heat treatment at 240 ℃, the fabricated 3D nickel foam coating could be refreshed from the damaged surface to superhydrophobic.

Special wettable nanostructured copper mesh achieved by a facile hot water treatment process

“…Therefore, polymer ligands containing thiol or fluorine functional groups of energy lower than water surface energy and higher than oils surface energy been enormously used to modified materials surface wettability and achieve surface superhydrophobicity and superoleophilicity [10][11][12]. Generally, surfaces with extreme wetting properties, such as superhydrophobic, superhydrophilic, superoleophobic, and superoleophilic surface have been found wide research interests due to their promising applications [13][14][15][16].…”

Synthesis of a Superhydrophobic Polyvinyl Alcohol Sponge Using Water as the Only Solvent for Continuous Oil-Water Separation

“…Moreover, many of them are undesirable due to the poor abilities in regeneration and recycling. Recently, a large variety of novel, efficient absorbents are becoming a hotspot in oil-water separation, such as carbon nanotubes (CNTs) [12][13][14], graphene-based materials [15][16][17], nanocellulose [18], polyurethane (PU) [19][20][21], and PVA-based absorbents [22].…”

Preparation of Parabolic Superhydrophobic Material for Oil-Water Separation

“…Wu et al [ 29 ] studied the preparation of superhydrophobic surfaces by spraying, dipping, painting and so forth, and used nanoparticles (i.e., SiO 2 or TiO 2 ) and epoxy resin as raw materials to simulate ordinary household coatings, which was easy to operate but the surface stability and the durability of the modification layer were often too poor. In order to improve these problems, wet etching [ 15 , 30 , 31 ] technology has been developed in recent years. Cao and co-workers [ 32 ] fabricated super-wettable surfaces on copper mesh and copper foam by etching with H 2 O 2 and HNO 3 and then immersed them into AgNO 3 solution, the Cu@Ag films were formed on copper substrates and exhibited superhydrophilicity and underwater superoleophobicity.…”