Bioinspired Multifunctional Foam with Self‐Cleaning and Oil/Water Separation

Abstract

Oil/water separation is a worldwide challenge. Learning from nature provides a promising approach for the construction of functional materials with oil/water separation. In this contribution, inspired by superhydrophobic self‐cleaning lotus leaves and porous biomaterials, a facile method is proposed to fabricate polyurethane foam with simultaneous superhydrophobicity and superoleophilicity. Due to its low density, light weight, and superhydrophobicity, the as‐prepared foam can float easily on water. Furthermore, the foam demonstrates super‐repellency towards corrosive liquids, self‐cleaning, and oil/water separation properties, possessing multifunction integration. We expect that this low‐cost process can be readily and widely adopted for the design of multifunctional foams for large‐area oil‐spill cleanup.

Superhydrophobic and superoleophobic properties in nature

“…This equation can also predict the possibility of achieving superhydrophobic properties from intrinsically hydrophilic materials (u Y w < 90 ) and even superoleophobic properties from intrinsically oleophilic materials (u Y oils < 90 ). Materials with superhydrophobic or superoleophobic properties are in extreme demand due to various potential applications such as in anti-corrosion coatings, anti-icing coatings, liquid-repellent textiles, oil/water separation, nanoparticles assembly, microfluidic devices, printing techniques, optical devices, high-sensitive sensors or batteries [6][7][8][9][10][11][12][13][14]. In many of these applications, the presence of an air layer trapped inside the surface roughness can reduce the liquid penetration (oil/water separation, anti-fogging), the ion penetration (anti-corrosion, water desalination, batteries), the heat transfer (anti-icing), while the surface roughness can improve the intrinsic properties of the materials (optical, electrical, catalytic properties).…”

Fe3O4/PS magnetic nanoparticles: Synthesis, characterization and their application as sorbents of oil from waste water

“…For example, a gas release and subsequent explosion occurred on the Deepwater Horizon oil rig in the Gulf of Mexico on April 20, 2010. The total crude oil release has been estimated at 4.9 million barrels [4]. The oil spill accidents and a large number of discharge of sewage containing oil which caused serious damage to the ecological environment of lakes and oceans not only seriously interfered with people's lives but also disrupt the normal business production , and the cost of cleaning up the oil is very expensive.…”

Underwater Self-Cleaning Scaly Fabric Membrane for Oily Water Separation

“…[4][5][6][7][8][9][10][11][12][13] Through rational design of surface structure and chemical composition, more and more multifunctional materials with special wettability have been fabricated and developed for oily wastewater separation. [14][15][16][17][18][19][20][21][22][23] By constructing the materials' surfaces with superhydrophobicity and superoleophilicity simultaneously, "oil-removal" type materials, such as organic polymer materials, [24][25][26][27][28][29][30][31] inorganic materials, [32][33][34][35][36] and other organic/inorganic hybrid materials [37][38][39][40][41][42] , have been developed for oily waste water separation. However, these "oil-removal" materials membranes are easily fouled, blocked up and even damaged by oils because of their intrinsic oleophilicity, resulting in a quick decrease in separation efficiency, flux, and membrane life, and even secondary pollution.…”