The effect of polar end of long-chain fluorocarbon oligomers in promoting the superamphiphobic property over multi-scale rough Al alloy surfaces

Abstract

Rough structures with re-entrant property and their subsequent surface energy reduction with long-chain fluorocarbon oligomers are both critical in developing superamphiphobic (SAP, i.e. both super hydrophobic and superoleophobic) surfaces. However, morphology of the lowsurface energy layer on a rough re-entrant substrate can strongly depend on the fluorocarbon oligomers used. In this study, the effect of polar end of different kinds of long-chain fluorocarbon oligomers in promoting a self-assembled monolayer with close packed molecules and robust adhesion on multi-scale rough Al alloy surfaces was investigated. Hierarchical Al alloy surfaces with microgrooves and nanograss structures were developed by a simple combination of one-directional mechanical sanding and post treatment in boiling de-ionized

Fabrication of a Highly Stable Superhydrophobic Surface with Dual-Scale Structure and Its Antifrosting Properties

“…As the third-richest element contained in the Earth’s crust, aluminum and its alloys possess dominant mechanical and physical advantages, such as superior ductility, high strength/weight ratio, easy formability, unique electronic and thermal conductivity, nonferromagnetic properties, excellent corrosion resistance, a nontoxic nature, and easy recyclability. − Therefore, their broad usage can be observed in a wide range of applications, especially in transportation aerospace, sensors, and household goods. − However, the intrinsic hydrophilicity of Al hampers its application in clammy environments, to a large extent. To address this difficulty, many superhydrophobic surfaces with superior water repellent properties have been fabricated on aluminum and its alloys.…”

“…Actually, many superhydrophobic coatings are incapable of having practical applications mainly ascribed to their inherent weakness toward mechanical abrasion, particularly the nanoscale roughness . For many reported superhydrophobic surfaces, slight attrition could destroy the superhydrophobicity, and some of them could not even withstand finger touching. ,, …”

Preparation of Superhydrophobic Multiscale Films for Oil-Water Separation in a Harsh Environment

“…Since the -CF 3 group at the end of the long chain of the FAS molecule has a lower surface free energy than the -CH 3 at the end of the STA, this difference in terminal groups helped to conclude that the reduction in surface energy will inevitably lead to an increase in contact angle when the surface roughness is the same [40]. However, such an excessively low surface tension of fluorine-containing material is disadvantageous for oil-water separation [41] because the FAS modified sample exhibited a certain degree of oleo-phobic property, and its contact angle between the sample and the diesel increased to 108 ± 0.7°.…”

Comprehensively durable superhydrophobic metallic hierarchical surfaces via tunable micro-cone design to protect functional nanostructures

“…Typically, there are three routes for producing superhydrophobic surfaces, namely, hydrophobic coatings, 17,18 hydrophobic bulk materials, [19][20][21][22][23] and micro/nanohierarchical structures with surface hydrophobic modications. [24][25][26][27][28] Hierarchical structures can be observed widely in nature as the results of billions of years of evolution, such as lotus leaves, sh scales, buttery wings, spider silk, etc. 29 Within these hierarchical structures developed by natural evolution, it is well understood that the nanostructures provide the main functionalities, such as wettability, directional adhesion, antireective properties, selective ltration, etc., whereas the microstructures provide the mechanical stability, strength and exibility responsible for supporting and protecting the functional nanostructures.…”