Annu Pandey

Multifunctional polyaniline–silver (Ag) nanocomposites were explored as a sustainable multifunctional material for environmental remediation and material protection applications. The nanocomposites achieved an efficient removal of fluorescein dye (89.6% ± 1.3%) under the selected experimental conditions of neutral pH, an initial dye concentration of 40 ppm, and an NC dose of 40 mg within 180 min at 60°C. The adsorption behavior was well explained by pseudo‐second‐order kinetics ( R ² = 0.9993) and Langmuir isotherm, exhibiting a maximum adsorption capacity of 52.8 mg g ^{− 1} . Anticorrosive performance studies on mild steel in 0.5 M HCl demonstrated superior protection by PANI–Ag nanocomposites in comparison with the garlic extract, with inhibition efficiencies of 85.04% and 82.2% from potentiodynamic polarization analysis and 82.1% and 62.0% from weight‐loss measurements, respectively. EIS results confirmed increased charge‐transfer resistance and the development of a protective film on the steel surface. Antioxidant evaluation using DPPH and ABTS assays revealed strong radical‐scavenging activity, achieving 87.91% ± 1.06% and 89.87% ± 1.32%, respectively, in methanol at a dose of 40 mg. These results highlight the ability of PANI–Ag nanocomposites to integrate dye remediation, corrosion protection and antioxidant functionality within a single multifunctional nanocomposite system, contributing to sustainable development goals (SDGs) 6, 9, and 12.

Green-synthesized multifunctional nanomaterials were developed with enhanced adsorption efficiency and antioxidant activity, demonstrating their potential for sustainable environmental applications.

This study introduces a green and sustainable method for synthesizing silver oxide nanoparticles (Ag ₂ O NPs) using Lobularia maritima extract as a natural reducing and stabilizing agent. Unlike traditional chemical and physical methods that rely on toxic reagents and high energy inputs, this eco-friendly approach is cost-effective, safer, and aligns with green chemistry principles. The synthesized Ag ₂ O NPs exhibited impressive antioxidant activity, with 80 ± 0.02% 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 75 ± 0.02% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging efficiencies, comparable to those of ascorbic and gallic acids. In photocatalytic tests, they achieved 91% degradation of methylene blue under visible light within 120 min, outperforming many chemically synthesized Ag ₂ O NPs. Characterization via ultraviolet-visible (UV–vis) spectroscopy, Fourier transform infrared (FTIR), scanning electron microscopy with energy dispersive x-ray analysis (SEM-EDX), dynamic light scattering (DLS), and x-ray diffraction (XRD) confirmed the high purity, stability, and controlled morphology of the samples. These findings highlight the potential of plant-based Ag ₂ O NPs for real-world applications in environmental cleanup and biomedical fields. Future research can focus on scaling production and testing biocompatibility for broader industrial use.

The green synthesis of nanoparticles offers a sustainable and eco-friendly alternative to traditional chemical methods. In this study, iron oxide nanoparticles (FeO-NPs) were successfully synthesized using Lagerstroemia indica flower extract as a natural reducing and stabilizing agent, with FeCl₃ serving as the precursor. Unlike conventional synthesis approaches that involve toxic chemicals, this method harnesses the plant’s rich phytochemicals to enhance nanoparticle stability and functionality. Comprehensive characterization techniques, including UV-Vis, FT-IR, SEM-EDX, DLS, and XRD, confirmed the spherical morphology, cubic crystalline structure, and bio-functionalized surface of FeO-NPs. FT-IR analysis revealed plant-derived functional groups aiding in nanoparticle stabilization, while SEM-EDX confirmed the elemental composition. The antioxidant potential of FeO-NPs was assessed through DPPH, ABTS, and TAC assays, demonstrating remarkable free radical scavenging activity (92.91% in DPPH, 89.52% in ABTS)—comparable to standard antioxidants like gallic acid and ascorbic acid. Furthermore, the anti-corrosion potential of FeO-NPs was investigated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The nanoparticles exhibited a maximum corrosion inhibition efficiency of 75.1% at a concentration of 20 mg, forming a protective layer on the metal surface and significantly reducing corrosion rates. This study not only introduces a novel and efficient plant-mediated approach for FeO-NP synthesis but also highlights their promising applications in biomedicine, environmental remediation, and industrial corrosion protection. By integrating nanotechnology with green chemistry, this work paves the way for developing sustainable, non-toxic, and multifunctional nanoparticles for a wide range of real-world applications.

This study presents the synthesis of polyaniline-coated silver (PANI-Ag) nanocomposites via in situ oxidative polymerization and their application in the removal of piracetam, an anti-Alzheimer drug, from aqueous solutions. The nanocomposites were characterized using XRD, FTIR, SEM-EDX, DLS, UV-Vis, and HRTEM. Adsorption experiments optimized key parameters, including pH (7), drug concentration (800 ppm), contact time (180 min), and temperature (65 °C), achieving a 99% removal efficacy. Kinetic and isotherm studies confirmed a Langmuir monolayer adsorption model with pseudo-second-order kinetics, indicating chemisorption. Additionally, the antioxidant activity of PANI-Ag nanocomposites was evaluated using DPPH (56.42%) and ABTS (76.43%) assays, demonstrating superior free radical scavenging compared to PANI alone. These findings highlight the dual potential of PANI-Ag nanocomposites as efficient drug removal agents and antioxidant materials, offering promising applications in environmental remediation and biomedical fields.

Green synthesis of iron oxide nanoparticles using Argemone mexicana leaf extract serves as a sustainable route. The biosynthesized nanoparticles exhibit strong antioxidant activity, demonstrating potential for therapeutic applications.