Fabrication of Durable Superhydrophobic Stainless Steel Mesh with Nano/Micro Flower-Like Morphologies for Self-Cleaning and Efficient Oil/Water Separation

Abstract

How to fabricate durable superhydrophobic materials for cyclic oil/water separation to solve oil-induced pollutions is still a problem. Herein, we fabricated a durable Superhydrophobic Stainless Steel Mesh (SH-SSM) with nano/micro flower-like sheets by self-assembly of zinc stearate for the cyclic separation of various oil/water mixtures. The SH-SSM exhibits durable superhydrophobicity against static or dynamic treatments. In virtue of durable superhydrophobicity of the SH-SSM, the dusts on surface of SH-SSM can be removed completely by running water immediately showing excellent self-cleaning performance. Moreover, the SH-SSM can be used to perform gravity-driven separation of heavy oil/water and light oil/water mixtures by utilizing its superhydrophobicity that oil phase penetrates the mesh and water phase is restricted. Separation efficiencies of the SH-SSM can reach 99.99%. After 20 cycles of separation, the separation efficiencies for are > 97.00% and > 98.25% for heavy oil/water and light oil/water mixtures, respectively. Flux values of dichloromethane, hexane and petroleum ether are 2.5 × 105 L m−2 h−1, 1.7 × 105 L m−2 h−1, and 1.8 × 105 L m−2 h−1, respectively. This study proposes a facial approach to prepare durable superhydrophobic and self-cleaning material for cyclic and fast separation of oil/water.

Visible-light-induced superhydrophilicity of crystallized WO3 thin films fabricated by using a newly isolated W6+ complex salt of citric acid

“…In this study, a tungsten oxide thin lm was rst formed using the MPM, in which a tungsten complex of citric acid was useful, and the resulting oxygen-decient WO 3 thin lm responded sensitively to weak Vis-light. Therefore, the oxygen-decient WO 3 thin lm formed using the MPM might also be applied to photocatalysts and oil separation 33,34 working under Vis-light and with energy conversion materials.…”

Superhydrophobicity on AISI 304 stainless steel through surface sensitization process and etching

“…The etching solution containing 5 mol L −1 HCl was used for 25 min, following the immersion in a 1 wt% FeCl 3 solution at 100 °C for four hours. In another work, with the aid of metal-organic frameworks (MOF) and stearic acid, Xu et al [25] successfully prepared a superhydrophobic stainless steel mesh with a WCA of 158.0 ± 1.2°and a WSA of 4.3 ± 0.6°. Stainless steel meshes were immersed in a solution containing zinc ions in 25 ml and imidazole in 160 mM solution for 24 h. After drying, the meshes were immersed in a solution of stearic acid and ethanol (2 wt%) for 24 h in order to reduce their surface energies.…”

Simple and Ultrahigh Efficient Superhydrophilic Polydopamine-coated TiO2 Cotton for Oil–water Separation

“…The process of oil-water separation is a kind of interfacial wetting [8]. According to the different wettability of some animal and plant surfaces to oil and water, researchers have developed a series of superwettability materials for oil-water separation [9][10][11][12][13]. The upper surface of the lotus leaf is Superhydrophobic/Superoleophilic (SHB/SOI) in air.…”