One-Step Preparation of Robust Superhydrophobic Foam for Oil/Water Separation by Pulse Electrodeposition

Abstract

Frequent leakage and pollution of oily wastewater seriously affect the world's ecosystem safety and economic development, which prompts us to urgently develop a highly effective, low-cost, wearresistant, chemically stable, and environmentally friendly new functional material for oil/water separation. In this paper, a robust superhydrophobic material was successfully electrodeposited on the porous copper foam substrates in myristic acid (CH 3 (CH 2 ) 12 COOH) and lanthanum chloride (LaCl 3 •6H 2 O) electrodeposition solution under a continuous pumping circulation and rotation condition. Moreover, SEM, EDS, XRD, FTIR, and XPS technologies were utilized to characterize the surface morphology and chemical composition information. The superhydrophobic property was evaluated by optical contact angle instrument and high-speed camera. It turned out that the micro/nanostructures were mainly composed of lanthanum myristate, and static CA of superhydrophobic copper foam (SCF) was up to 165.2°with SA ≈ 2°. Besides, the SCF exhibited a better performance with good anticorrosion, excellent chemical stability, and outstanding mechanical stability. Furthermore, the SCF can achieve up to 98.6% oil/water separation efficiency. More importantly, by employing this novel processing method, it can effectively save time and provide a promising potential way to make denser and thicker foams for continuous oil/water separation and may be easily applied to other conductive metal matrix materials.

High Efficient Construction and Comprehensive Evaluation of Superhydrophobic Filter Screen Coatings

“…When DC voltage is applied to the electrodes, part of stearic acid combines with free Ce 3+ ions near the cathode to form cerium stearate complex and hydrogen ions (H + ). With the progress of electrodeposition, the concentration of free hydrogen ions around the cathode plate increases, some of which obtain electrons to form hydrogen gas, while cerium stearate complex is deposited on the surface of the cathode filter screen [17,31]. The reaction process is described by the following formulae:…”

“…Electrodeposition method has the advantages of low cost, good reproducibility, easy control, fast, and efficient [15,16]. In particular, one-step electrodeposition can generate low surface energy materials while constructing rough structure, so as to quickly prepare superhydrophobic films on the substrate surface [17][18][19]. Compared with postdeposition modification, it not only simplifies the preparation process but also makes the modification of low surface energy materials more compact and uniform.…”

“…Compared with postdeposition modification, it not only simplifies the preparation process but also makes the modification of low surface energy materials more compact and uniform. Zhang et al [17] prepared fluoride-free functionalized superhydrophobic 3D porous copper foam by one-step pulse electrochemical deposition method, showing excellent corrosion resistance, mechanical strength, and oil/water separation performance. Yang et al [20] prepared nickel corrosionresistant superhydrophobic coating on copper by direct current electrodeposition.…”

Superhydrophobic and Conductive Foams with Antifouling and Oil–Water Separation Properties

“…The diversification of fillers, including zero-dimensional particles (e.g., copper) and two-dimensional sheets (e.g., graphene (GR)), can reinforce wetting while conferring antifouling and conductive propertiesenabling a broad spectrum of applicability. For example, compared to other one-dimensional (1D) and two-dimensional (2D) materials, 3D porous polymeric materials with special wettability (i.e., superhydrophobic and superoleophilic) have attracted enormous attention for use in oil–water separation applications owing to their high porosity, oil/organic solvent adsorption capacity, and separation efficiency (SE). , To date, many methods of fabricating these oil-adsorbing materials have been developed, including electrospinning, spray coating, dip-coating, hydrothermal, electrochemical, chemical vapor deposition, separation, in situ polymerization, and high-internal-phase emulsions methods . However, most of these methods require harsh conditions, complex fabrication processes, special instruments, hazardous solvents, high energy consumption, poor recyclability, low absorption capacity, and poor separation efficacy, which increase production costs and limit their practical applications.…”

Smart Hierarchical Zeolitic Imidazolate Framework-Coated Stainless Steel Meshes with Switchable Wettability for Oil/Water Separation

“…In recent years, the environmental problems that arose from oil spills and oily wastewater have become increasingly serious. It should be of great significance to find efficient ways for treatment of oily wastewaters. − Traditional separation methods including centrifugation, adsorption, skimming, and microbial degradation have been used in separation of oil/water mixtures. However, they suffer from some drawbacks such as inefficiency with the generation of secondary pollutions.…”