Search

Ecosystems worldwide face a serious and life-threatening water crisis due to water contamination. Nanotechnology offers a promising solution to this issue by providing methods for removing pollutants from aquatic sources. In this study, we utilized a green and simple approach to biosynthesize NiSe NPs using Hibiscus rosa-sinensis extract as the bio-source. The plant extract acts as a reducing, stabilizing, and capping agent in the synthesis process. A simple hydrothermal method was employed to blend the NiSe NPs photocatalysts. UV-Visible DRS spectroscopy was utilized to confirm the reduction in and stabilization of Ni2+ and Se2− ions. The resulting NiSe NPs have a bandgap of 1.74 eV, which facilitates electron and hole production on their surfaces. To characterize the functional groups on the NiSe NPs and their surface interactions with bio-compounds, FTIR spectroscopy was utilized. XRD analysis revealed the crystallite size of the NiSe NPs to be 24 nm, while FE-SEM and TEM imaging showed their spherical shape and material distribution. EDX spectroscopy confirmed the integrity of the NiSe NPs' material. XPS analysis provided information on the chemical composition, nickel and selenium valency, and their interface. The efficacy of the NiSe NPs as a blended photocatalyst in photodegrading Methylene Blue (MB) dye was tested under visible light, resulting in 92% degradation. Furthermore, the NiSe NPs exhibited bactericidal activity against Escherichia coli and Staphylococcus aureus bacteria due to their advanced oxidation and reduction in charge particles, which increased the degradation efficiency and suppressed cell proliferation. Based on the obtained findings, the NiSe NPs show promise as a powerful agent for water remediation and microbial resistance. [ABSTRACT FROM AUTHOR]

The green synthesis of metal oxide nanoparticles is an efficient, simple, and chemical-free method of producing nanoparticles. The present work reports the synthesis of Murraya koenigii-mediated ZrO2 nanoparticles (ZrO2 NPs) and their applications as a photocatalyst and antibacterial agent. Capping and stabilization of metal oxide nanoparticles were achieved by using Murraya koenigii leaf extract. The optical, structural, and morphological valance of the ZrO2 NPs were characterized using UV-DRS, FTIR, XRD, and FESEM with EDX, TEM, and XPS. An XRD analysis determined that ZrO2 NPs have a monoclinic structure and a crystallite size of 24 nm. TEM and FESEM morphological images confirm the spherical nature of ZrO2 NPs, and their distributions on surfaces show lower agglomerations. ZrO2 NPs showed high optical absorbance in the UV region and a wide bandgap indicating surface oxygen vacancies and charge carriers. The presence of Zr and O elements and their O=Zr=O bonds was categorized using EDX and FTIR spectroscopy. The plant molecules' interface, bonding, binding energy, and their existence on the surface of ZrO2 NPs were established from XPS analysis. The photocatalytic degradation of methylene blue using ZrO2 NPs was examined under visible light irradiation. The 94% degradation of toxic MB dye was achieved within 20 min. The antibacterial inhibition of ZrO2 NPs was tested against S. aureus and E. coli pathogens. Applications of bio-synthesized ZrO2 NPs including organic substance removal, pathogenic inhibitor development, catalysis, optical, and biomedical development were explored. [ABSTRACT FROM AUTHOR]

Water pollution is a serious concern for developing and undeveloped countries. Photocatalytic degradation of organic pollutants is an effective degradation method to restrain the green ecosystem. This research article presents a green, low-cost, and benevolent eco-friendly biosynthesis of cobalt oxide (Co3O4) nanoparticles using Curcuma longa plant extract. The UV and visible region absorbance of Co3O4 nanoparticles estimated the Co2+ and Co3+ transitions on the lattice oxygen, and their bandgap of 2.2 eV was confirmed from the UV-DRS spectroscopy. The cubic structure and spherical shape of Co3O4 nanoparticles were estimated by using XRD and TEM characterizations. Plant molecules aggregation and their agglomerations on the nanoparticles were established from FTIR and EDX spectroscopy. Multiple cobalt valences on the oxygen surfaces and their reaction, bonding, and binding energies were analyzed from XPS measurements. The biogenic Co3O4 nanoparticles were executed against gram-positive (Staphylococcus aureus—S. aureus) and gram-negative (Escherichia coli—E. coli) bacteria. A gram-positive bacterial strain exhibited great resistivity on Co3O4 nanoparticles. Degradation of organic dye pollutants on the Co3O4 nanoparticles was performed against methylene blue (MB) dye under the conditions of visible light irradiation. Dye degradation efficiency pseudo-first-order kinetics on the pseudo-first-order kinetics denotes the rate of degradation over the MB dye. This research work achieved enhanced degradation potency against toxic organic dye and their radicals are excited from visible light irradiations. Absorption light and charged particle recombinations are reformed and provoked by the plant extract bio-molecules. In this process, there is no inferior yield development, and electrons are robustly stimulated. Furthermore, the biosynthesized Co3O4 nanoparticles determined the potency of bacterial susceptibility and catalytic efficacy over the industrial dye pollutants. [ABSTRACT FROM AUTHOR]

Aspergillus parasiticus (A. parasiticus) is known for producing aflatoxins and is a major threat to the food industry. Green synthesis of nanoparticles (NPs) is a cost-effective and environment-friendly approach. A variety of NPs have been explored as antifungal agents; however, their antifungal characteristics need to be further enhanced to compete with traditional fungicides. The present work describes the green synthesis of ZnO and CuO NPs by precipitation method using aqueous leaf extract of Manilkara zapota and their surface modification through polyaniline (PANI). Still, there is no published study on the application of PANI-coated particles as antifungal agents against A. parasiticus and hence was the focus of this work. The polymer-coated NPs were synthesized, characterized, and investigated for their antifungal properties against A. parasiticus. Textural and structural characterization of PANI-coated and non-coated ZnO and CuO NPs were confirmed through FT-IR, SEM, and XRDtechniques. The PANI-coatedNPs presented higher fungal growth inhibition (%) as compared to the non-coated ones. The maximum inhibition of 77 ± 2% (n = 3) was shown by PANI/ZnO NPs at a concentration of 12 mmol L-1 and 72 h of incubation. The non-coated NPs presented a lower inhibition rate with respect to their coated NPs, thus justifying the role of polymeric coating in improving antifungal efficiency. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) is one of the important materials in conducting polymers (CPs) for significant applications in devices due to its unique properties such as high electrical conductivity, flexibility, and economical price. In this work, novel and eco-friendly green synthesis of polyaniline Nanorod (PANI-NR) were developed by solar irradiation approach in acidic medium without the aid of any surfactant and template. As characterized by morphology studies, the average diameter of PANI-NR is approximately 200–250 nm and length is 2–2.5 µm. The elemental analysis and structural geometry of PANI-NR are examined through EDX, Mapping, and XRD studies. The electrochemical properties were investigated using CV, GCD, and EIS techniques. The electrochemical performance of Cyclic voltammetry analysis shows the redox peaks which confirms the PANI-NR has excellent electrical conductivity. A specific capacitance of 25 F/g at 10 mV/s scan rate by CV studies and 106 F/g at 1 A/g current density by GCD studies is observed for One-Dimensional (1D) PANI-NR as an electrode material for supercapacitor. Also, it shows remarkable cyclic retention and stability. These results indicate that PANI-NR is expected to have better electrochemical performance in energy storage applications. ga1 • Facile and eco-friendly synthesis of polyaniline Nanorod (PANI-NR) was developed by solar irradiation approach for the first time. • The synthesized PANI-NR has excellent electrochemical performance. • Symmetric supercapacitor based PANI-NR electrode shows specific capacitance of 106 F/g at 1 A/g and remarkable cycling stability. [ABSTRACT FROM AUTHOR]

This paper reports a facile route to synthesis of zinc oxide (ZnO) nanoparticles assembled into marigold shaped clusters utilizing the Eucalyptus globulus leaf extract. Synthesized ZnO marigold shaped clusters were examined as catalyst for photocatalytic degradation of non-degradable organic dyes under the natural sunlight. The structural properties of as-synthesized ZnO marigold shaped clusters were demonstrated by powder-X-ray diffraction confirming the high crystallinity with hexagonal phase. Moreover, detailed structural and crystallographic analyses for as-synthesized ZnO marigold shaped clusters were analyzed through Rietveld refinement using FULLPROF software which further confirmed the wurtzite-type structure with P63mc space group. Field emission scanning electron microscopy was utilized to investigate the morphology of the synthesized ZnO, which revealed that nanoparticles assembled in clusters and eventually transformed into marigold shaped structures. Transmission electron microscopy analysis demonstrated that as-synthesized ZnO marigold shaped clusters consist of spherical and hexagonal nanoparticles with average crystallite size of 6 ± 2 nm. The role of Eucalyptus globulus leaf extract for the formation of ZnO clusters was discussed in detail by the plausible reaction mechanism. As-synthesized ZnO marigold shaped clusters exhibited the excellent photocatalytic behavior by observing almost 98 % photocatalytic performance towards organic dyes under open air sunlight condition. The aim of such investigation of the synthesized ZnO clusters has potential as solar based photocatalytic application towards efficient degradation of organic dyes. [Display omitted] • A sustainable approach to synthesis of ZnO marigold shaped clusters. • Eucalyptus globulus leaf extract utilized for the facile synthesis. • Demonstration to the catalytic properties of the ZnO marigold shaped clusters under the open air sunlight. [ABSTRACT FROM AUTHOR]