Honey-assisted synthesis of CuFe2O4 nano pebbles: a sustainable approach to photocatalytic and antibacterial activity

Chapter 14 - Impact of the rare earth elements doping on the copper ferrite spinel magnetic nanoparticles

The present study describes a relative comparison of antimicrobial and photocatalytic activity in titania encapsulated nickel ferrite nanoparticles with different dopants. The photocatalytic and antimicrobial activity in doped titania composite nanoparticles follows the sequence: W4+ doped > Nd3+ doped > Zn2+ doped > undoped titania. The maximum enhancement in tungsten doped titania is attributed to the greater inhibition of electron hole recombination process and decrease in band gap in titania. The ferrite magnetic nanoparticles encapsulated with the photocatalytic shell retain superparamagnetic characteristics and magnetic strength encouraging their potential application as removable antimicrobial photocatalytic composite nanoparticles. The combination of reverse micelle and hydrolysis method is recognised as a promising method for the synthesis of these composite nanoparticles.

Ternary composite of TiO2 nanotubes/Ti plates modified by g-C3N4 and SnO2 with enhanced photocatalytic activity for enhancing antibacterial and photocatalytic activity

Effect of various capping agents on photocatalytic, antibacterial and antibiofilm activities of ZnO nanoparticles

This study explores the effect of zinc (Zn) content on the physicochemical characteristics, photocatalytic activity, and antibacterial activity of hydrothermally synthesized hydroxyapatite (HAp). Zinc doped HAp (Zn-HAp) was synthesized with varying Zn content of 1, 2 and 5 wt%, and characterized using XRD, FTIR, UV-Vis DRS, TEM, and zeta potential analysis. Characterization results showed that Zn was successfully dopped into the HAp structure without forming its own ZnO phase, with a decrease in crystallite size and band gap. Photocatalytic activity test was conducted by degradation of tetracycline (TC) antibiotic using UV light. The results show that Zn-HAp has higher photocatalytic activity than pure HAp, with the highest degradation efficiency of 90.48% obtained at 1Zn-HAp. The photocatalytic activity increased as the band gap decreased, which was facilitated by Zn doping. In addition, antibacterial tests against Escherichia coli and Staphylococcus aureus showed that Zn-HAp had a larger inhibition zone than pure HAp, indicating an increase in antibacterial activity, especially at higher Zn concentrations. HIGHLIGHTS Zinc-doped hydroxyapatite with a varied zinc have been synthesized by hydrothermal method. Increasing Zn content in Zn-HAp affects to reduce crystallite size and band gap energies The reduced band gap energy leads to the enhanced photocatalytic activity. Zn-HAp samples show the higher tetracycline photocatalytic activity compared to HAp at 90.84 %. Zn-HAp samples showed good antibacterial activity against Eschericia coli and Staphylococcus aureus. GRAPHICAL ABSTRACT

Antibacterial photocatalytic activity of different crystalline TiO2 phases in oral multispecies biofilm

In the present investigation we have studied the role of varying pH and sintering temperature on the properties of copper ferrite nanoparticles synthesized from metal nitrate solutions by sol–gel auto-combustion technique. The CuFe2O4 samples were synthesized with varying pH values (without maintaining pH, pH 4 and 8). The careful analysis of X-ray diffraction (XRD) result showed that the pH provides boost to develop copper ferrite nanoparticles. The samples without maintaining pH suggested the presence of three different phases. The samples with pH values 4 and 8 showed the tetragonal structure. Crystal structure phase transformation of copper ferrite (pH 8) nanoparticles was studied under different sintering conditions. The prepared samples were characterized by XRD, field emission scanning electron microscopy, FTIR and magnetization. These copper ferrite nanoparticles sintered at different temperatures show combinations of cubic and tetragonal phases. The thermal behavior of as-prepared samples was confirmed by thermo gravimetric/differential thermal analyzer analysis. The morphology of materials was understood by SEM technique. The room temperature magnetic measurement proves strong redistribution of Cu2+ ions. Sintering temperature alerts the saturation magnetization (Ms) to a large extent from 9.26 to 25.15 emu/g.

In this work, we have successfully prepared copper ferrite (CuFe2O4) nanoparticles through a modified sol–gel method by of copper (II) nitrate, iron (III) nitrate, and starch as starting materials in water as solvent. The formation of as-produced nanoparticles and their structure, shape and elemental composition were analyzed by means of several techniques including X-ray diffraction, energy dispersive X-ray microanalysis, scanning electron microscopy, and ultraviolet–visible spectroscopy. The magnetic properties of as-prepared copper ferrite nanoparticles were also investigated with vibrating sample magnetometer. In addition, methyl orange was chosen as a dye water pollution to evaluate its degradation by as-synthesized copper ferrite (CuFe2O4) nanoparticles under ultraviolet light irradiation. The photocatalysis results reveal that the decolorization of 53 % for methyl orange occurred with CuFe2O4 nanoparticles in 90 min under ultraviolet light irradiation.

Enhanced photocatalytic activity of titanium-doped copper ferrite for methyl green dye degradation under commercial visible LED light

α-Arylation of oxindoles using recyclable metal oxide ferrite nanoparticles: Comparison between the catalytic activities of nickel, cobalt and copper ferrite nanoparticles

Construction of high efficient g-C3N4 nanosheets combined with Bi2MoO6-Ag photocatalysts for visible-light-driven photocatalytic activity and inactivation of bacterias

In this study, we prepared reduced graphene oxide (rGO)/titanium dioxide (TiO2)/nickel ferrite (NiFe2O4) nanocomposites with different mass ratios of rGO, TiO2, and NiFe2O4 by a simple hydrothermal method. These nanocomposites were found to exhibit enhanced visible light harvesting, reduced electron–hole recombination, and improved magnetic properties compared to rGO, TiO2, and NiFe2O4. The study evaluated the photocatalytic and antibacterial activity of the nanocomposites, with particular emphasis on the GTN211 (with a mass ratio of 2:1:1 for rGO:TiO2:NiFe2O4) nanocomposite. The results showed that the GTN211 nanocomposite exhibited the best photocatalytic performance under both UV and visible light irradiation, achieving 95 and 89% degradation of Methylene Blue dye in 15 min, respectively. The study also investigated the photodegradation mechanism using various scavengers and found that holes were the main active species in the process. In addition to photocatalytic activity, the GTN211 nanocomposite also showed good antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria, with the minimum inhibitory concentration of 1 mg mL−1 for both bacteria and a minimum bactericidal concentration of 0.8 and 1 mg mL−1, respectively. Hence, the GTN211 nanocomposite has potential as a material for environmental remediation and biomedical applications. The combination of photocatalytic and antibacterial activity makes this material a promising candidate for a wide range of applications.

Ferrite magnetic materials have emerged as capable materials in engineering, research, and medicine because of their exclusive and fascinating properties obtained from a variety of synthesis techniques. These ferrites are significant in commercial products, research, and biomedical applications. Green synthesis methods for ferrite nanocomposites and nanoparticles are becoming increasingly popular due to their usefulness in a range of industries, engineering, environmental, and medicinal remediation. Ferrite nanoparticles and nanocomposites (MFe 2 O 4 , where M = Ni, Cu, Mg, Co, Zn, and Mn) have recently gained popularity due to their many uses in biological, environmental, and chemical interactions. This review covers the most recent investigations over the last few years on green‐synthesized ferrite nanoparticles, ferrites containing nanocomposites, and more elements, with a focus on microorganism‐mediated and plant‐based synthesis processes. The surface features of ferrite nanoparticles synthesized from green materials are discussed, as is their potential for sensors, energy, water treatment, antibacterial activity, biological, and heavy metal removal applications. This article presents an inclusive overview of green‐synthesized ferrites, including the most recent research advances and findings. To fully realize the promise of nanoferrites in several fields, a thorough understanding of green manufacturing, properties, and applications is essential. Green‐synthesized ferrites are chosen due to their potential for improved control over particle size and shape, lower cost, decreased toxicity, and environmental friendliness, all of which preserve magnetic properties that are better than those of conventionally synthesized ferrites, making them a more sustainable choice for a range of applications.

We report the efficient biogenic synthesis of silver nanoparticles (Ag NPs) using silver nitrate and extracts of different parts of Theobroma cacao: the husk (h-Ag NPs), pulp (p-Ag NPs), and seed (s-Ag NPs). In addition, we have tested the antibacterial and photocatalytic activities of the Ag-NPs. The Ag NPs obtained from husk, pulp, and seed extracts show variation in the particle size, dispersion, and morphology. UV–visible absorbance measurements reveal surface plasmon resonance bands at 425, 438, and 462 nm for the s-Ag, h-Ag, and p-Ag NPs, respectively. Transmission electron microscopy studies revealed the formation of monodisperse spherical Ag NPs with diameter ranging from 6 to 18 nm. Fourier transform infrared measurements of the as-synthesized Ag NPs indicate differences in the phytochemicals decorating the NP surfaces, which led to differences in the zeta potential, hydrodynamic radius, and polydispersity index. The p-Ag, h-Ag, and s-Ag NPs exhibited photocatalytic activity on exposure to sunlight from sun, achieving 35%, 29%, and 24% degradation of methylene blue (MB) within 60 min, respectively. Further, the p-Ag NPs showed 98.3% MB photodegradation after 180 min. The photocatalytic rate constants for the degradation of MB were also calculated. Finally, we found that the biogenic nanoparticles affect bacterial growth, possibly by causing protein leakage and cell death. The p-Ag NPs showed better antibacterial activity against Bacillus subtilis and Escherichia coli than h-Ag and s-Ag. The photocatalytic and antibacterial activities of the Ag NPs synthesized with T. cacao mainly depend on the particle size and the biomolecules on the surface of the NPs.

Enhanced photocatalytic and antibacterial activity of ZnO with rice field crab chitosan and plectranthus amboinicus extract