Bio‐Inspired Multifunctional Metallic Foams Through the Fusion of Different Biological Solutions

Abstract

Nature is a school for scientists and engineers. Inherent multiscale structures of biological materials exhibit multifunctional integration. In nature, the lotus, the water strider, and the flying bird evolved different and optimized biological solutions to survive. In this contribution, inspired by the optimized solutions from the lotus leaf with superhydrophobic self‐cleaning, the water strider leg with durable and robust superhydrophobicity, and the lightweight bird bone with hollow structures, multifunctional metallic foams with multiscale structures are fabricated, demonstrating low adhesive superhydrophobic ­self‐cleaning, striking loading capacity, and superior repellency towards different corrosive solutions. This approach provides an effective avenue to the development of water strider robots and other aquatic smart devices floating on water. Furthermore, the resultant multifunctional metallic foam can be used to construct an oil/water separation apparatus, exhibiting a high separation efficiency and long‐term repeatability. The presented approach should provide a promising solution for the design and construction of other multifunctional metallic foams in a large scale for practical applications in the petro‐chemical field. Optimized biological solutions continue to inspire and to provide design idea for the construction of multiscale structures with multifunctional integration.

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.…”

Fabrication of filter paper with tunable wettability and its application in oil–water separation

“…In this composite contact mode of solid/oil/water, the triple-phase contact line is discontinuous [31], consequently, the filter paper exhibits underwater superoleophobic property, and the oil droplet can easily roll off the filter paper, which may be used to selectively separate water from oil. Compared with superhydrophilic/superoleophobic materials, materials with superhydrophobicity/superoleophilicity are more typical oil-removing materials which have been widely used for oil-water separation during the past decades [4,5,33]. Properties of superhydrophobic and superoleophilic will make an oil phase spread (adsorb or penetrate) easily on the materials while the water phase will be repelled, thus separating oils from an oil-water mixture [3].…”

Multiple-dimensional micro/nano structural models for hydrophobicity of butterfly wing surfaces and coupling mechanism

“…Table 1). Regarding the complex wettability, the butterfly wing surface resembles the lotus leaf [27] and the rice leaf [19] with low adhesion and high hydrophobicity, but differs greatly from the peanut leaf [16], the rose petal [17], the cicada wing [28] and the gecko feet [29] with high adhesive superhydrophobicity. The micrometric scales play a crucial role in the complex wettability of the butterfly wing surfaces.…”