The production of zinc oxide nanoparticles (ZnO NPs) utilizing different vegetable extracts (onion, cabbage, carrot, and tomato) was performed in this research owing to its excellency over other methods of synthesis, namely, simplicity, environmental friendliness, and the elimination of harmful compounds. Fresh extracted onion, cabbage, carrot, and tomato of ZnO NPs are characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-visible spectroscopy. FTIR findings demonstrate that the prepared nanoparticles were observed in the spectrum of 626 cm-1–1219 cm-1 with some other functional groups. Wurtzite hexagonal structure of the prepared ZnO NPs was observed from XRD results. In addition, the prepared nanoparticles were failed into nanoscales (17 nm, 18 nm, 24 nm, and 15 nm) calculated from Scherrer’s equation. Nearly spherical shapes were seen from SEM image for onion and tomato extraction while rod and tube for carrot and cabbage, respectively. Two broad peaks were observed from UV-vis spectroscopy results for each extract. The presence of a wide range of energy bandgaps in the region of 3-4 eV was detected, indicating that ZnO NP material can be employed in metal oxide semiconductor-based systems. The dye-sensitive solar cell based on ZnO NPs has been successfully synthesized, and the efficiency of the device has been evaluated by measuring the current density-voltage behaviour under the presence of artificial sunshine. The increased effectiveness of the manufactured dye-sensitive solar cell is attributable to a large improvement in dye molecular adsorption onto the surface of ZnO NPs. Thus, the usage of the green produced ZnO NPs with creating dye sensitivity solar cell is a simple and viable way for the well-being of our future.

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Ultraviolet radiation causes damages to the human body, such as skin ageing, skin cancer, and allergies throughout the world. Applying zinc oxide nanoparticles (ZnO NPs) in sunscreen products (like cloths or textiles) to protect human skin by absorbing the ultraviolet radiations that emerged from the sun. The main aim of this study is to investigate both absorbance and transmittance characteristics of the untreated and treated cotton textiles. For ZnO NPs using hydrothermal methods, they were made from Zn(NO3)2·6H2O and NaOH at a constant annealing temperature of 300°C. Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-vis spectroscopy were used to analyze the produced ZnO NPs. From the FT-IR result, ZnO NPs were observed in the region of 400-600 cm-1. Wurtzite hexagonal structure of ZnO NPs with the average crystal size 32 ± 49  nm was observed from XRD results. Flowers in the shape of synthesized ZnO NPs were observed from SEM images. The UV-vis penetration peaks were identified at 264 nm and 376 nm, with energy band gaps of 4.68 and 3.536 eV, respectively. When compared to bulk ZnO, the energy band gap of ZnO NPs was blue-shifted due to the impact of quantum confinement. The peaks in UV-vis absorption were caused by an electronic transition from the valiancy to the conduction bands. The high energy band shows high absorbance of the synthesis sample in the case of 264 nm. The ZnO NPs were manufactured and applied to 100% of raw cotton to impart sunscreen action to both untreated and treated cotton fabrics. The performance of treatment has been evaluated utilizing UV-vis spectroscopy through quantifying ultraviolet protective factors (UPF) and percentage of transmitted (%T) radiations. The treated cotton textiles have 61.50% UPF while 2.65% ultraviolet radiations were transmitted. In other words, untreated cotton textiles have 1.63% UPF while 74.56% ultraviolet radiation was transmitted. Therefore, the treated cotton textiles have excellent protection categories when compared to untreated cotton textiles.

A green deposition method of zinc oxide nanoparticles using coffee leaf extraction was successfully prepared. The use of these preparation techniques is accepted by many researchers because it is nonexpensive and simple and has no environmental impact during the operation. The determination and reduction of Zn ions to ZnO NPs were characterized by using a UV-visible spectroscope. The UV-visible spectroscopy result reveals that the large band gap energy is observed in the visible region at the wavelength of 300 nm. X-ray diffraction and SEM analysis confirm that the deposited nanoparticle is highly crystalline with (111), (222), and (100) planes and cubic shape structure. The coffee leaf extraction serves as a reducing agent for stability of the particle length, where its medicinal value outcome showed an important antibacteria of the pathogenic type which appeared on the wound. The present research deals with the green synthesis of ZnO NPs as well as its application in toxicity reduction.

Silver nanoparticles in the range from 1 to 100 nm are widely used in industrial applications as catalysis, electronics, and photonics, and they have unique properties such as optical, electrical, and magnetic characteristics that can be used as antimicrobial, biosensor textile, cosmetics, composite fibers, and electronic components and to amend shelf life of food substances. The main objective of the present review was to focus on formulation methods of silver nanoparticles with recent advances and future aspects. Silver nanoparticle shows very high potential towards biological applications. Several physicals, chemical, and various biological techniques have been employed to synthesize and stabilize silver nanoparticles. For the manufacture of silver nanoparticles, multiple methods, including chemical simplification with different natural and inorganic decreasing agents, physicochemical reduction, electrochemical procedures, and radiolysis, are employed. Silver nanoparticles are the single most manufacturer-identified material that can be used in all nanotechnology products. They can be used in food packing polymers to enhance the shelf lifespan. The present review is aimed at different types of synthesis and details of silver nanoparticles used as drug delivery vehicles, antibacterial activity, toxicity, recent advances, and future aspects.

Titanium dioxide nanoparticles (TiO2 NPs) were prepared by Caricaceae (Papaya) Shell extracts. The Nanoparticles were analyzed by UV–Vis spectrums, X-ray diffractions, and energy-dispersive X-rays spectroscopy analyses with a scanning electron microscope. An antifungal study was carried out for TiO2 NP in contradiction of S. sclerotiorums, R. necatrixs and Fusarium classes that verified a sophisticated inhibitions ratio for S. sclerotiorums (60.5%). Germs of pea were individually preserved with numerous concentrations of TiO2 NPs. An experience of TiO2 NPs (20%, 40%, 80% and 100%), as well as mechanisms that instigated momentous alterations in seed germinations, roots interval, shoot lengths, and antioxidant enzymes, were investigated. Associated with controls, the supreme seeds germinations, roots and plant growth were perceived with the treatments of TiO2 NPs. Super-oxide dis-mutase and catalase activities increased because of TiO2 NPs treatments. This advocates that TiO2 Nanoparticles may considerably change antioxidant metabolisms in seed germinations.

Comparison of green and chemical precipitation method syntheses of zinc oxide nanoparticles (ZnO NPs) was performed, and antimicrobial properties were investigated. Avocado, mango, and papaya fruit extracts were carried out for the green synthesising methods, while the chemical precipitation method was chosen from chemical synthesis methods. Zinc nitrate was used as a salt precursor, whereas leaf extract was served as a reducing agent for green synthesising methods. In addition, sodium hydroxide, polyvinyl alcohol, and potassium hydroxide were used as reducing agents in the case of chemical precipitation synthesis methods. ZnO NPs were characterised by characterizing techniques such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The antimicrobial activities of prepared nanoparticles were evaluated on Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus), and Salmonella typhimurium (S. typhimurium). The particle sizes of the prepared samples which were evaluated by the Scherrer equation were in the range of 11-21 nm for green synthesis, while 30-40 nm for chemical precipitation synthesis methods. Small agglomerations were observed from SEM results of prepared ZnO NPs from both methods. Prepared ZnO NPs were showed strong antimicrobial properties. From the result, the inhibition zone was in the range of 15-24 mm for the green route and 7–15 mm for chemical precipitation methods, where the standard drugs have 25 mm of the zone of inhibition. A green synthesised method of preparing ZnO NPs gives promising antimicrobial properties compared to chemical synthesis and is also eco-friendly and safe compared to the chemical synthesis.

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