Anticorrosive polyaniline-coated copper oxide (PANI/CuO) nanocomposites with tunable electrical properties for broadband electromagnetic interference shielding

Active corrosion protection of epoxy coating filled with surface-engineered cellulose nanocrystals with polyaniline

Cellulose nanocrystal (CNC) grafted from polyaniline (PANI) doped with phosphate (PO43-) anion, designated here by C-pP, was employed as an active anticorrosive nanoparticle in epoxy (EP) coating at a concentration of 1 wt% for the mild-steel substrate. The presence of the phosphate agents on the backbone of PANI was confirmed by Fourier transform infrared spectroscopy (FT-IR) and further supported by thermogravimetric analysis (TGA). Electrochemical impedance spectroscopy (EIS) measurements for coatings with an artificial scratch revealed that EP/C-pP coating can provide an inhibition efficiency of up to ~69 %, about twice that of EP/PANI coating. Furthermore, the adhesion of the optimal sample was 3 MPa, more than those of EP/PANI and EP coatings. Additionally, the presence of C-pP drastically improved the hydrophobicity of the epoxy coating with an increase in its contact angle from 42.4 ̊ to 92.4 ̊. The superior anticorrosion property of EP/C-pP was attributed to the presence of CNC, which promoted the dispersion of PANI molecules within the EP matrix (confirmed by FE-SEM); resulting in 1) improved barrier effect against corrosive agents, and 2) self-healing property arising from the smart release of phosphate dopants from the PANI backbone under basic conditions and forming protective complexes at the infected areas.

Green synthesis and characterization of CuO/PANI nanocomposite for efficient Pb (II) adsorption from contaminated water

This study presents the synthesis of a green polymer-based nanocomposite by incorporating green CuO nanoparticles into polyaniline (PANI) for the adsorption of Pb (II) ions from contaminated water. The nanocomposite was extensively characterized using FTIR, XRD, BET, SEM-EDX, XPS, and Raman spectroscopy, both before and after Pb(II) adsorption. Optimization studies were performed to assess the effects of key parameters, including pH, adsorbent dosage, and initial ion concentration on the adsorption process. Adsorption isotherms and kinetic models were applied to analyze the experimental data, revealing that the Freundlich isotherm provided the best fit, with a high correlation coefficient (R²) and a (1/n) value less than 1, indicating favorable adsorption conditions. Furthermore, the Avrami and pseudo-first-order kinetic models demonstrated superior fitting compared to other models. The green nanocomposite exhibited outstanding adsorption capacity, highlighting its potential as a sustainable and efficient adsorbent for Pb(II) removal from wastewater.

Synthesis of an eco-inspired anticorrosive composite for mild steel applications

We synthesised a polyaniline/mica (Mica-PANI) nanocomposite using naturally occurring muscovite mica by a top-down approach. The developed coating materials were characterised using a different technique to investigate their chemical and structural properties using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). Furthermore, the electrochemical properties of the coating materials were investigated by linear sweep voltammetry (LSV). SEM images elucidate the composite's average particle diameter of the prepared nano-mica, approximately 80 nm. The existence of relevant functional groups and bonding in the prepared Mica-PANI composite material was confirmed by means of XPS and FTIR techniques. Moreover, the synthesised composite with 5% w/w shows high anticorrosion protection, i.e. 84 μm per year, compared to competing materials, including commercial paint and individual raw materials (0.35 mm per year). The anti-corrosive effect occurs mainly due to two opposing effects: the formation of an Fe(OH)3 passive layer on the steel surface by oxidation of surface iron atoms by the PANI and the barrier effect of mica NPs through inhibition of corrosive agents. Therefore, the eco-inspired composite could be an ideal cost-effective coating material to prevent the corrosion of mild steel surfaces.

Surface Characterization and Electrical Properties of Low Energy Irradiated PANI/PbS Polymeric Nanocomposite Materials

In this work, nanocomposite samples of polyaniline (PANI) and lead sulfide nanoparticles (PbSNPs) were prepared, utilizing the solution preparation method, for implantation in energy storage elements. The PANI/PbS films were irradiated by different fluences of oxygen beam: 5 × 1016, 10 × 1016, and 15 × 1016 ions.cm−2. The composite was investigated by XRD, SEM, DSC, and FTIR. After ion irradiation, the Tg and Tm values decreased by 4.8 °C and 10.1 °C, respectively. The conductivities, electrical impedances, and electrical moduli of untreated and irradiated samples were examined in frequencies ranging from 102 Hz to 5 MHz. Moreover, the ion beam caused a modification in the dielectric characteristics of PANI/PbS. The dielectric constant ε′ was improved from 31 to 611, and the electrical conductivity increased from 1.45 × 10−3 S/cm to 25.9 × 10−3 S/cm by enhancing the fluence to 15 × 1016 ions.cm−2. Additionally, the potential energy barrier, Wm, decreased from 0.43 eV to 0.23 eV. The induced changes in the dielectric properties and structural characteristics of the PANI/PbS samples were determined. These modifications provide an opportunity to use irradiated PANI/PbS samples for several applications, including microelectronics, batteries, and storage of electrical energy.