Single step green synthesis of nickel and nickel oxide nanoparticles from Hordeum vulgare for photocatalytic degradation of methylene blue dye

Integrating thermodynamics towards bulk level synthesis of nano Ni catalysts: a green mediated sol–gel auto combustion method

Novel strategy for the environmentally benign bulk level synthesis of nickel nanoparticles.

Scavenging of Organic Pollutant and Fuel Generation through Cost-Effective and Abundantly Accessible Rust: A Theoretical Support with DFT Simulations

Waste management and energy generation are the foremost concerns due to their direct relationship with biological species and the environment. Herein, we report the utilization of iron rust (inorganic pollutant) as a photocatalyst for the photodegradation of methylene blue (MB) dye (organic pollutant) under visible light (economic) and water oxidation (energy generation). Iron rust was collected from metallic pipes and calcined in the furnace at 700 °C for 3 h to remove the moisture/volatile content. The uncalcined and calcined rust NPs are characterized through scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier-transform infrared (FTIR) analysis, X-ray Diffraction (XRD), and thermogravimetric analysis (TGA). The morphological study illustrated that the shape of uncalcined and calcined iron rust is spongy, porous, and agglomerated. The XRD and DLS particle sizes are in a few hundred nanometers range. The photodegradation (PD) investigation shows that calcined rust NPs are potent for the PD of modeled MB, and the degradation efficiency was about 94% in a very short time of 11 min. The photoelectrochemical (PEC) measurements revealed that calcined rust NPs are more active than uncalcined rust under simulated 1 SUN illumination with the respective photocurrent densities of ~0.40 and ~0.32 mA/cm². The density functional theory simulations show the chemisorption of dye molecules over the catalyst surface, which evinces the high catalytic activity of the catalyst. These results demonstrate that cheaper and abundantly available rust can be useful for environmental and energy applications.

Green Nanotechnology: Recent Research on Bioresource-Based Nanoparticle Synthesis and Applications

In the last decades, the idea of green nanotechnology has been expanding, and researchers are developing greener and more sustainable techniques for synthesizing nanoparticles (NPs). The major objectives are to fabricate NPs using simple, sustainable, and cost-effective procedures while avoiding the use of hazardous materials that are usually utilized as reducing or capping agents. Many biosources, including plants, bacteria, fungus, yeasts, and algae, have been used to fabricate NPs of various shapes and sizes. The authors of this study emphasized the most current studies for fabricating NPs from biosources and their applications in a wide range of fields. This review addressed studies that cover green techniques for synthesizing nanoparticles of Ag, Au, ZnO, CuO, Co3O4, Fe3O4, TiO2, NiO, Al2O3, Cr2O3, Sm2O3, CeO2, La2O3, and Y2O3. Also, their applications were taken under consideration and discussed.

In vitro Antimicrobial Activity of Biogenically Synthesized Nickel and Zinc Nanoparticles against Selected Pathogenic Bacterial Strains

Bacterial resistance to already present antibiotics demands for new approaches in field of medicine. Scientists prefer nanoparticles (NPs) due to their promising potential in many applications. Two bacterial strains, Escherichia coli and Bacillus subtilis were used for biogenic synthesis of NPs. Characterization of prepared NPs was accomplished using UV-vis spectroscopy and fourier transform infrared spectroscopy (FTIR). The prepared NPs were confirmed by the color change from pale yellow to having white deposition for Zn NPs while from dark green to light green for Ni NPs. UV-vis spectroscopy of E. coli and B. subtilis based ZnNPs showed highest peak at 354nm and 362nm, respectively. Likewise, E. coli and B. subtilis NiNPs showed peaks at 246 nm and 238 nm, respectively. Antibacterial activity of B. subtilis based ZnNPs showed significant (p ≤ 0.05) zone of inhibition (ZOI; 27.3±0.6) against B. subtilis and 26.66±0.67 against E. coli at 100 mg/mL. Antibacterial activity of E. coli based ZnNPs showed 8.3±0.3 ZOI against B. subtilis and 6.6±0.3 ZOI against E. coli while NiNPs showed (25.0±0.0 mm) (ZOI) against B. subtilis and (25.0 ± 0.3 mm) against E. coli. Minimum inhibitory concentration (MIC) of E. coli ZnNPs showed values of 6.7±0.3 μg/mL for E. coli and 4.7±0.3 μg/mL for B. subtilis. MIC of B. subtilis ZnNPs showed 5.3±0.3 μg/mL for E. coli and 6.6±0.3 μg/mL for B. subtilis while NiNPs showed 33.0±1.0 μg/mL against E. coli and 24.0±1.0 μg/mL against B. subtilis as effective inhibitory concentrations. Minimum bactericidal concentration (MBC) of E. coli ZnNPs showed 7.3±0.3 μg/mL for E. coli and 8.3±0.3 μg/mL for B. subtilis. MBC of B. subtilis ZnNPs showed 7.6±0.3 μg/mL for E. coli and 8.6±0.3 μg/mL for B. subtilis while NiNPs showed 45.7±1.3 μg/mL against E. coli and 33.0±1.0 μg/mL against B. subtilis as effective inhibitory concentrations. It was concluded from the current study that biogenically synthesized ZnNPs and NiNPs are effective as promising antibacterial agents and have potential applications in biomedical fields.

Remediation of microplastics using bionanomaterials: A review

Pollution by microplastics (MPs) formed by the physicochemical breakdown of plastics are a worldwide issue with long-lasting and hazardous natural effects. The natural expulsion of MPs takes several years and can be dangerous. Several effective technological innovations have been developed over the years to remediate harmful MPs. Among them, a blend of nanotechnological techniques using bionanomaterials has been investigated to a large extent. The objective of this review is to compile the MPs found in the environment and bionanomaterial-based approaches for their removal. This information is important for researchers who are exploring the adverse consequences of MPs and their remediation and developing advanced eco-friendly strategies to control and eradicate MPs in the future. The control and eradication of MPs depend on all of us; hence, the proper awareness of MPs pollution must be provided to every individual, as all of us are a part of the environment.

Bioinspired NiO Nanospheres: Exploring In Vitro Toxicity Using Bm-17 and L. rohita Liver Cells, DNA Degradation, Docking, and Proposed Vacuolization Mechanism

The present work demonstrated a novel Cleome simplicifolia-mediated green fabrication of nickel oxide nanoparticles (NiO NPs) to explore in vitro toxicity in Bm-17 and Labeo rohita liver cells. As-fabricated bioinspired NiO NPs were characterized by several analytical techniques. X-ray diffraction (XRD) revealed a crystalline face-centered-cubic structure. Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible diffuse reflectance spectroscopy (UV-DRS), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirmed NiO formation. The chemical composition was confirmed by energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy. Brunauer-Emmett-Teller (BET) revealed the mesoporous nature. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the formation of 97 nm diameter nanospheres formed due to the congregation of 10 nm size particles. Atomic force microscopy (AFM) revealed the nearly isotropic behavior of NiO NPs. Further, a molecular docking study was performed to explore their toxicity by binding with genetic molecules, and it was found that the docking energy was about -9.65284 kcal/mol. On evaluating the in vitro toxicity of NiO NPs for Bm-17 cells, the study showed that when cells were treated with a high concentration of NPs, cells were affected severely by toxicity, while at a lower concentration, cells were affected slightly. Further, on using 50 μg/mL, quick deaths of cells were observed due to the formation of more vacuoles in the cells. The DNA degradation study revealed that NiO NPs are significantly responsible for DNA degradation. For further confirmation, trypan blue assay was observed for cell viability, and morphological assessment was performed using inverted tissue culture microscopy. Further, the cytotoxicity of NiO NPs in L. rohita liver cells was studied. No toxicity was observed at 1 mg/L of NiO NPs; however, when the concentration was 30 and 90 mg/L, dark and shrank hepatic parenchyma was observed. Hence, the main cause of cell lysis is the increased vacuolization in the cells. Thus, the present study suggests that the cytotoxicity induced by NiO NPs could be used in anticancer drugs.

Green synthesis of zinc ferrite nanoparticles for photocatalysis of methylene blue

In this study, zinc ferrite nanoparticles (ZF-NPs) were synthesized using aqueous seed extract of Piper nigrum as a bio-reducing and stabilizing agent. FTIR, SEM, FE-SEM, XRD, and TGA have been used for characterizing ZF-NPs. The results showed that Piper nigrum stabilized ZF-NPs have high purity and size range of 60-80 nm. The performance of the ZF-NPs has been investigated by photocatalytic reduction of methylene blue (MB) in the presence of sunlight. The factors responsible for affecting the degradation values of the reaction were also explored for developing a better understanding of the phenomenon.