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Titanium type lithium ion‐sieve nanotubes synthesized by the hydrothermal method were extensively explored over recent years due to its promising properties. However, on account of nanotubes′ tangled structure impeding the lithium adsorption in the interior nanotube walls, unalterable dimensions of the synthesized nanotubes, and a long period of annealing, the anodizing technique was proposed. It is shown that lithium uptake and adsorption capacity is improved because of easier mass transfer during the ion exchange process. This work focuses on a novel anodizing method for nanotube ion‐sieve synthesis. The optimum anodizing condition was discovered by altering anodizing voltage, time, and fluoride concentration to have a proper nanotube morphology and corresponding high surface area for achieving the most suitable adsorption properties. Nanotubes were grown on Ti foil in Ethylene Glycol (EG) electrolyte with different amounts of NH4F in a range of anodizing voltage (40–70 V) and time (1–4 hours). TiO2 Nanotube array morphology, dimension, and phase characterization were derived from FESEM and XRD analysis. As a result, the optimum condition discovered in this research to obtain acceptable morphology and high aspect ratio nanotubes was at 0.5 wt % NH4F, 40 V, 3 hours. Lithium titanate spinel with nanotube morphology was synthesized by chemical lithiation in the LiOH solution and then acid‐treated to obtain H4Ti5O12 adsorbent. ICP‐OES analysis revealed that the H4Ti5O12 lithium‐ion sieve with nanotube array structure obtain adsorption capacity up to 37.5 mg/g in LiOH and LiCl solutions (112 mg/L Li, pH 12), designating that the Hydrogen titanate (HTO) ion sieve could effectively extract Li+from the enriched solutions.

A hierarchical superhydrophobic surface is prepared via a two-step boiling water immersion process and anodization of the treated aluminum substrate in a novel hydrophobic electrolyte of aluminum nitrate and stearic acid mixture at room temperature. The immersion time in boiling water had a significant influence on the morphology and durability of the sample. A pseudoboehmite coating is created on the aluminum surface during the boiling process, as revealed by the field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectrophotometer results. The energy-dispersive x-ray spectroscopy analysis confirmed the formation of hydrophobic coating surface after anodization. Also, the FE-SEM images and the atomic force microscopy (AFM) investigation proved the hierarchical nano-and microstructure stem from boiling and anodizing procedures, respectively. The successively boiled and anodized surface exhibited contact angle of about 155˚, sliding and hysteresis contact angles of <5˚and 2˚, respectively. It also demonstrated a self-cleaning property and remarkable durability.

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Superhydrophobic surfaces demonstrate significant characteristics which make them suitable for a wide variety of applications. In this study, we propose a facile, one-step, and cost-effective anodizing scheme using aluminum nitrate/stearic acid mixture solution to create a superhydrophobic surface on an aluminum mesh. The surface outperforms the surface anodized by the widely used oxalic acid solution in terms of superhydrophobicity and water-surface friction behavior. The proposed surface reduced the friction by 11% on average respective to the surface prepared by oxalic acid. The durability of the introduced superhydrophobic surface has also been investigated. The proposed surface retained its high water contact angle and showed higher hydrophobicity relative to the surface anodized by oxalic acid after ten abrasion cycles. This method and surface may be used for numerous applications due to its ease of fabrication, low cost, and excellent performance in energy-loss reduction.