PEO Coatings Modified with Halloysite Nanotubes: Composition, Properties, and Release Performance

Abstract

In this work, the properties of the coatings formed on the Mg-Mn-Ce alloy by plasma electrolytic oxidation (PEO) in electrolytes containing halloysite nanotubes (HNTs) were investigated. The incorporation of halloysite nanotubes into the PEO coatings improved their mechanical characteristics, increased thickness, and corrosion resistance. The studied layers reduced corrosion current density by more than two times in comparison with the base PEO layer without HNTs (from 1.1 × 10–7 A/cm2 to 4.9 × 10–8 A/cm2). The presence of halloysite nanotubes and products of their dihydroxylation that were formed under the PEO conditions had a positive impact on the microhardness of the obtained layers (this parameter increased from 4.5 ± 0.4 GPa to 7.3 ± 0.5 GPa). In comparison with the base PEO layer, coatings containing halloysite nanotubes exhibited sustained release and higher adsorption capacity regarding caffeine.

Effect of Hydrothermal and Vapor Thermal Treatments on Apatite Inductivity of Titanate Nanotubes on Anodized Ti–5Nb–5Mo Surface

“…Ti alloys are bioinert and do not bond well to bones after implantation into the human body [9]. In recent years, researchers have adopted multiple surface modification methods, including electrospinning [10], sol-gel [11], sputtering [12], electrophoretic deposition [13], plasma electrolytic oxidation (PEO) [14][15][16], and anodic oxidation [17] methods. Among them, the anodization method can produce ordered TiO 2 nanotubes, which have a large specific surface area [18].…”

The effect of silica NPs incorporation on protective properties of oxide layers formed by PEO on Mg97Y2Zn1 alloy with LPSO-phase

“…It is well known that the use of various substances in the form of particles as a dispersion phase of the electrolyte under PEO is one of the most effective ways to improve the protective and functional properties of oxide coatings, as well as to increase the productivity and efficiency of the PEO technology [ [18] , [19] , [20] , [21] , [22] , [23] , [24] ]. The using of SiO 2 , ZrO 2 , TiN, Si 3 N 4 , TiO 2 , TiC, MoS 2 particles, carbon nanotubes or halloysite nanotubes as additions to the electrolyte during PEO has led to significant improvement of wear- and corrosion resistance of formed oxide layers [ 21 , [25] , [26] , [27] , [28] , [29] , [30] ]. Silicon dioxide in a nanoscale form is one of the most proven substances as an additive to the electrolyte in the PEO of aluminum, magnesium and titanium alloys.…”

The Effect of Silver and Samarium on the Properties of Bioglass Coatings Produced by Pulsed Laser Deposition and Spin Coating

“…Another challenge is the risk of immune rejection or other complications that can arise when foreign materials are introduced into the body. Researchers in this field use various biomaterials, including ceramics and polymers, with specific properties, such as biocompatibility, bioresorbability, bioavailability, and adequate physicochemical, biological, and mechanical properties, to create scaffolds that support the growth and differentiation of cells [3][4][5].…”