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Polyaniline (PANI) incorporating titanium dioxide (TiO2), silicon dioxide (SiO2) and zinc oxide (ZnO) were successfully synthesized via an ultrasonic-assisted in-situ chemical oxidative polymerization technique. This method significantly enhances the dispersion and interaction of metal oxides (MOs) within the PANI matrix. Detail analysis of the structural, morphological, thermal, and electrical properties of nanocomposites revealed substantial enhancements. XRD and FTIR results confirmed the successful incorporation of MOs into the PANI matrix, evidenced by the reduction in peak intensities. Morphological studies via FESEM highlighted the impact of MOs on the PANI microstructure, particularly the notable agglomeration of TiO2. DLS results demonstrated variations in particle size distributions, with SiO2 and ZnO contributing to reduced particle sizes, while TiO2 increased the average particle size due to aggregation. Thermal analysis via TGA and DSC revealed enhanced thermal stability of the nanocomposites compared to pure PANI, with SiO2/PANI exhibiting the highest stability. Electrical conductivity measurement demonstrated that the SiO2/PANI nanocomposite exhibited the highest performance, with a conductivity of 0.43 S/cm, attributed to the effective interaction between SiO2 and PANI which facilitates electron transfer. Electrochemical studies, including Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS), further confirmed the superior electrochemical performance of the SiO2/PANI nanocomposite, showing the highest current response and the lowest charge transfer resistance. These findings highlight the novel synthesis method and the enhanced properties of MO/PANI nanocomposites, presenting significant advancements for advanced technological applications. [ABSTRACT FROM AUTHOR]

The primary goals of human civilization are sustainable growth and restoration of the ecosystem. Currently, the continuous release of effluents containing heavy metals from tanneries, and the mining, printing, and pharmaceutical industries into the aquatic environment has become a serious issue. Chromium (Cr) and mercury (Hg) pose a major threat to human beings. Several techniques have been employed to mitigate this threat, including adsorption, electrolysis, chemical precipitation, desalination, reverse osmosis, ion exchange, membrane filtration, and photocatalysis. However, photocatalysis is known for its cost-effectiveness and green aspects in the removal of heavy metal ions from solutions. Over the last few decades, there has been a growing interest among researchers worldwide to study this technique. Numerous materials, including conducting polymers (CPs), have been utilized for the removal of heavy metal ions from wastewater/aqueous solutions. Polyaniline (PANI)-based nanocomposites are effective photocatalysts for the removal of various types of heavy metal ions from wastewater/aqueous solutions. Despite its potential, several factors affect the removal efficiency, such as irradiation levels and the type of PANIbased nanocomposite used. Further research is needed to address these challenges and improve the stability and reusability of PANI-based photocatalysts. Given the available water resources in the real world, it is critical that in-depth research be conducted into PANI-based photocatalysts, and the stability and reusability of such catalysts and achieving the primary goals of human civilization, namely sustainable growth and ecosystem restoration. [ABSTRACT FROM AUTHOR]

Effects of various molar ratios of monomer (aniline), oxidant (ammonium peroxydisulfate), and dopant (hydrochloric acid) on the polymerization of polyaniline (PANI) were investigated using direct ultrasonic irradiation technique. The effects of varying molar ratio of dopant and oxidant on the structural stability, morphology, and electrical conductivity of the prepared PANI were studied. Firstly, a scheme derived from electrical conductivity point of view, by varying the molar ratio of ammonium peroxydisulfate (APS). As the molar ratio of APS to aniline (ANI) varied from 0.1 to 1.25, the conductivity of PANI reached a maximum of 0.24 S/cm at a ratio of 1. Thereafter, by fixing the optimized molar ratio of APS and aniline the molar ratio of hydrochloric acid (HCl) was varied. The conductivity of PANI increased with an increase of HCl concentration and reached a maximum of 0.5 S/cm at an HCl concentration of 2 M. Finally, the formation mechanism for polymerization of PANI were discussed using Fourier transform infrared spectra, ultraviolet–visible spectra, nuclear magnetic resonance spectroscopy, and X‐ray diffraction spectroscopy. The final product is in protonated form, possessing structural stability and electrically conductive. [ABSTRACT FROM AUTHOR]

Recycled polypropylene/polyaniline/graphene nanoplatelets (rPP/PANI/GNPs) nanocomposites were fabricated via ultrasonic-assisted single-screw extruder at 150–170 °C with a rotating screw speed of 50 rpm. The ultrasonic wave frequency and power supply were kept constant at a frequency of 20 kHz and 6 kW, respectively. The composition of the polymer nanocomposites used in this study was 92 wt.% rPP and 8 wt.% PANI, denoted as rPP/PANI. The effects of GNPs loadings (0.5, 1.5, and 3.0 parts per hundred resin (phr)) on the structural, morphological, thermal, and electrical properties on the nanocomposites were systematically evaluated. The X-ray diffraction (XRD) and fourier transform infrared spectroscopy (FTIR) showed the presence of GNPs characteristics at 26.5°, 42.40°, 54.51°, and interactions between GNPs and rPP/PANI nanocomposites at different GNPs loadings. The compatibility of GNPs in rPP/PANI nanocomposites was confirmed by the morphological study, which showed to an enhancement in the electrical properties of the nanocomposites. The results also showed that the incorporation of 3 phr GNPs into rPP/PANI nanocomposites resulted in a lower degree of crystallinity of about 20.8% and a higher electrical conductivity of about 4.1 × 10–1 S cm−1. The current work paves a way towards understanding how to effectively enhance the electrical conductivity of rPP/PANI nanocomposites using GNPs, leading to potential use in electronic applications. [ABSTRACT FROM AUTHOR]

A novel sonochemical method has been applied to prepare Polyaniline (PANI) from aniline monomers. PANI was synthesized via ultrasonic irradiation (U.I) by varying the sonication (reaction) time. Surface morphology and electrical conductivity were studied using FESEM and Four-probe conductivity meter and structural properties were examined using FT-IR and UV-VIS. The presence of characteristic bonds of PANI was observed from FTIR spectroscopy technique. The findings of this study reveal the importance of sonication time in shaping the morphology, particle sizes and electrical conductivity of the PANI. The morphology of the generated PANI indicated granular structure. On the other hand, the electrical conductivity of the nanocomposite increased up to 1.78 S/cm at 30 min of sonication and then decreased with further increase in sonication time. Sonochemical synthesis route is a multifaceted technique using which nanostructured materials with different physical and chemical characteristics can by produced. This can be achieved by just varying the treatment condition (e.g., ultrasonic irradiation time, amplitude, temperature) during sonication. Therefore, this study provides the optimized sonication time for PANI synthesis. The output of this research clearly shows that, ultrasonication is a one of the fast, versatile, emerging, and promising non-destructive green technology which still needs to be understood completely. [ABSTRACT FROM AUTHOR]