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The durability of antimicrobial agents and its effectiveness is the most important factor for consumer usage. One important class of antimicrobial agents are inorganic metals and their metal oxides which can be prepared into nanoparticles and can be imparted to enhance the antimicrobial properties. The purpose of this paper is to investigate the effect of three different polymeric binders during the application of zinc oxide (ZnO) nanoparticles on the antimicrobial and performance properties of the finished fabric.

In this study, ZnO nanoparticles were prepared by a wet chemical method. The nano-particles size distributions was determined using Nanoplus Dynamic Light Scattering particle size distribution analyzer and concentration of nano ZnO 0.1% (w/v) was applied with 2% (w/v) polymeric binders, namely, polyvinyl alcohol (PVA), polyurethane (PU) and butyl acrylic (BA) on cotton fabric by pad dry cure method. The treated samples were tested for physical properties such as tearing strength, tensile strength, crease recovery and air permeability and antimicrobial properties using test method American Association of Textile Chemists and Colorists (AATCC) 100. Further, the content of zinc in the treated samples was determined by the atomic absorption method. The treated fabric was analyzed using fourier transform infrared spectroscopy and scanning electron microscopic and also tested for cytotoxicity as per International Organization for Standardization 10993.

The results indicated that the type of polymeric binders did not show any influence on the uptake of the zinc content. All treated samples showed positive results >99% with regard to antibacterial property. However, the polymeric treated samples showed a difference in physical properties. The ZnO nano-finish reduced the tensile strength and tearing strength of the fabrics. The difference in crease recovery for samples ZnO/PVA and ZnO/PU was not much except for ZnO/BA where it increased by 38%. The air permeability decreased after application for all treated samples, the lowest among treated samples was in ZnO/PU fabric. Further, ZnO/PVA finished fabric was found to retain antibacterial property up to 50 washes and was effective against MS2 Bacteriophage as a surrogate virus when analyzed as per AATCC 100–2012 test method, and therefore can be potentially used as health-care apparel such as doctors coat and scrub suits.

The outcome of this research is in its contribution to the field of reusable textiles. It highlights the use of nanotechnology to design and develop cotton fabrics for antimicrobial properties which has the potential of preventing the growth of harmful bacteria. The study brings forth the use of ZnO nanoparticles mixed with PVA binder on 100% cotton fabrics which exhibits antibacterial and antiviral properties with adequate wash durability. Currently, there is a high demand of effective durable textiles with barrier properties and the present study provides a promising solution to provide reusable textiles with a greater level of protection.

The low resistance against penetration of water, oxygen and the other corrosive ions through the paths of coating is one the most important problems. So, protective properties of coating such as polyester must be promoted. Recently, the use of nanoparticles in the matrix of polymer coating to increase their protection and mechanical properties has been prospering greatly. The purpose of this study is to improve the corrosion resistance of the polyester powder coating with ZnO nanoparticles. The ZnO nanoparticles have been synthesized by hydrothermal method in a microwave. Using polyester – ZnO nanocomposite coating as powder – combining them by ball milling process and coating them by electrostatic process are innovative ideas and have not been used before it.

Polyester powder as the matrix and ZnO nanoparticles as reinforcing were combined in three different weight percentage (0.5, 1, 2 Wt.%), and they formed polymer nanocomposite by ball milling process. Then, the fabricated nanocomposite powder was applied to the surface of carbon steel using an electrostatic device, and then the coatings were cured in the furnace. The morphology of synthesized zinc oxide nanoparticles was investigated by transmission electron microscope. Also, the morphology of polyester powder and fabricated coatings was studied by scanning electron microscope. The effects of zinc oxide nanoparticles on the corrosion resistance of coated samples were studied by electrochemical impedance spectroscopy (EIS) test at various times (1-90 days) of immersion in 3.5 per cent NaCl electrolyte.

Scanning electron microscopy (SEM) results reveal that there are no obvious crack and defects in the nanocomposite coatings. In contrast, the pure polyester coatings having many cracks and pores in their structure. According to the EIS results, the corrosion resistance of nanocomposite coating compared to pure coating is higher. The value obtained from EIS test show that corrosion resistance for coating that contains 1 Wt.% nanoparticle was 32,150,000 (Ωcm²), which was six times bigger than that of pure coating. In addition to providing a barrier against diffusion of electrolyte, ZnO nanoparticles act as a corrosion inhibitor and, thus, increases the corrosion resistance. The corrosion resistance of coating containing 0.5 Wt.% nanoparticles was lower as compared to that of 1 Wt.% nanoparticles. The low content of nanoparticles caused partial covering of the porosity of coating which in turn leads to provide weaker barrier properties. The increase in quantity of nanoparticles from 1 to 2 Wt.% also caused a decrease in corrosion resistance which is attributed to the agglomeration of nanoparticles.

The results of this study indicated the significant effect of ZnO nanoparticles on the protective performance and corrosion resistance of the polyester powder coating. Evaluation of coating surface and interface with SEM technique revealed that nanocomposite coating compared with pure polyester coating provided a coating with lower number of pores and with higher quality. The EIS measurements represented that polymeric coating that contains nanoparticles compared to pure coating provides a better corrosion resistance. In addition to providing a barrier against diffusion of electrolyte, ZnO nanoparticles act as a corrosion inhibitor and thus increase the corrosion resistance. The corrosion resistance of coating containing 0.5 Wt.% nanoparticles was lower as compared to that containing 1Wt.% nanoparticles. The low content of nanoparticles caused partial covering of the porosity of coating which in turn leads to provide weaker barrier properties. The increase in quantity of nanoparticles from 1 to 2 Wt.% also caused a decrease in corrosion resistance which is attributed to the agglomeration of nanoparticles.

The textile industry is evolving toward nanotechnology, which provides materials with self-cleaning properties. This paper aims to provide a thorough explanation of the green synthesis and mechanism of ZnO nanoparticles, with prospective applications of zinc oxide nanoparticles (ZnO NPs) in self-cleaning textiles.

This review introduces a green mechanism for the synthesis of ZnO NPs using plant extracts, their self-cleaning properties and the mechanisms of physical, chemical and biological self-cleaning actions for textile applications.

ZnO NPs are among the several nanoparticles that are beneficial for self-cleaning textiles because of their exceptional physical and chemical properties, although review publications addressing the use of ZnO NPs in textiles for self-cleaning are uncommon. These results indicate that the plant-synthesized ZnO NPs display excellent biological, physical and chemical self-cleaning properties, the mechanism of which involves photocatalysis, surface roughness and interactions between ZnO NPs and bacterial surfaces.

Nanoformulations of plant-synthesized ZnO have been reviewed to achieve promising self-cleaning textile properties and have not been reviewed earlier.

Studies on this topic have shown the remarkable lubricating properties, viz. friction-reducing and anti-wear, of certain nanoparticles. This makes them potential candidates for replacing the lubrication additives currently used in automobile lubricants, especially because the latter is known to be pollutants and less efficient in some specific conditions. This has not gone unnoticed to professionals in the sector, including those commercializing these additives, the oil companies and the car industry, all of whom are following this burgeoning research area with keen interest. All of them are faced with the problem of providing lubricants that meet the needs of the technological evolution of engines while respecting ever-stricter environmental norms.

The impact of copper oxide (CuO) and zinc oxide (ZnO) nanoparticles on the tribological properties of the SAE-40 pure diesel oil is studied in this paper. The two nanoparticles are not oxide or deteriorate with the base oil. The average size of CuO and ZnO nanoparticles is 40 and 20 nm, respectively. Nanoparticle concentrations of 0.1 Wt.%, 0.2 Wt.%, 0.3 Wt.%, 0.4 Wt.% and 0.5 Wt.% are tested using a pin-on-disk tribometer to evaluate their impact on friction and wear. The test is carried out at different loads and rotating speeds of 58.86 N and 300 rpm, 39.24 N and 500 rpm and 78.48 N and 900 rpm at room temperature, respectively.

The obtained results of the nanolubricants are compared with those of pure diesel oil in terms of % improvement in tribological properties. However, it is observed that an increase in the nanoparticle concentrations does not guarantee to enhance the tribological properties. Similarly, increasing the applied load and the rotating speed does not lead to improving the anti-friction and anti-wear properties. The results obtained revealed that the optimal improvements in the anti-friction and anti-wear properties of the pure oil are 69% and 77% when CuO nanoparticle concentrations of 0.3 Wt.% and the ZnO nanoparticle concentrations of 0.1 Wt.% are used, where the applied load and rotating speed are 39.24 N and 500 rpm, respectively. It has also been noticed that the CuO nanolubricants have a significant impact on the anti-friction property compared with ZnO nanolubricants.

All these nanoparticles have been the subject of detailed investigation in this research and many key issues have been tackled, such as the conditions leading to these properties, the lubrication mechanisms coming into play, the influence of parameters such as size, structure and morphology of the nanoparticles on their tribological properties/lubrication mechanisms and the interactions between the particles and the lubricant co-additives. To answer such questions, state-of-the-art characterization techniques are required, often in situ, and sometimes an extremely complex set up. Some of these can even visualize the behavior of a nanoparticle in real time during a tribological test. The research on this topic has given a good understanding of the way these nanoparticles behave, and we can now identify the key parameters to be adjusted when optimizing their lubrication properties.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2022-0234/

This study aims to explore the synergistic effect of oxide nanoparticles (ZnO, Fe₂O₃, SiO₂) and cerium nitrate inhibitor on anti-corrosion performance of epoxy coating. First, cerium nitrate inhibitors are absorbed on the surface of various oxide nanoparticles. Thereafter, epoxy nanocomposite coatings have been fabricated on carbon steel substrate using these oxide@Ce nanoparticles as both nano-fillers and nano-inhibitors.

To evaluate the impact of oxides@Ce nanoparticles on mechanical properties of epoxy coating, the abrasion resistance and impact resistance of epoxy coatings have been examined. To study the impact of oxides@Ce nanoparticles on anti-corrosion performance of epoxy coating for steel, the electrochemical impedance spectroscopy has been carried out in 3% NaCl solution.

ZnO@Ce3+ and SiO2@Ce3+ nanoparticles provide more enhancement in the epoxy pore network than modification of the epoxy/steel interface. Whereas, Fe2O3@Ce3+ nanoparticles have more to do with modification of the epoxy/steel interface than to change the epoxy pore network.

Incorporation of both oxide nanoparticles and inorganic inhibitor into the epoxy resin is a promising approach for enhancing the anti-corrosion performance of carbon steel.

This study aims at evaluating the properties of cotton fabric after nanofinishing using zinc oxide and silicon dioxide nanoparticles along with dimethylol dihydroxyethylene urea (DMDHEU).

DMDHEU recipes was optimized by Box-Behnken Design before using it with nanoparticles. These nanoparticles were synthesized by sol gel technique and applied to the fabric by pad-dry-cure method. The treated samples were evaluated for functional properties such as self-cleaning, antibacterial and ultraviolet (UV) protection properties.

Due to the use of DMDHEU, crease recovery property was obtained. The results showed good antibacterial property against S-aureus (gram positive) bacteria and E-coli (gram negative). UV protection property of combined nano-finished samples showed good results, as they showed very low transmission of UV-irradiation when exposed to UV-rays compared to single nanoparticle finished samples. Self-cleaning property of finished cotton was found to be good even after five washing cycles.

In this study, nanofinishing of cotton fabric with zinc oxide and silicon dioxide nanoparticles along with DMDHEU was studied to achieve promising functional properties with long durability of nanofinishing not studied earlier.

The purpose of this paper is to study the effect of doping, annealing temperature and visible optical excitation on CuO-ZnO nanocomposites’ acetone sensing properties and introduce an attractive candidate for acetone detection at about room temperature.

ZnO nanoparticles doped with CuO were prepared by sol-gel method, and the structure and morphology were characterized via X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and Brunauer-Emmett-Teller. The photoelectric responses of CuO-ZnO nanocomposites to cetone under the irradiation of visible light were investigated at about 30°C. The photoelectric response mechanism was also discussed with the model of double Schottky.

The doping of CuO enhanced performance of ZnO nanoparticles in terms of the photoelectric responses and the gas response and selectivity to acetone of ZnO nanoparticles, in addition, decreasing the operating temperature to about 30ºC. The optimum performance was obtained by 4.17% CuO-ZnO nanocomposites. Even at the operating temperature, about 30ºC, the response to 1,000 ppm acetone was significantly increased to 579.24 under the visible light irradiation.

The sensor fabricated by 4.17% CuO-ZnO nanocomposites exhibited excellent acetone-sensing characteristics at about 30ºC. It is promising to be applied in low power and miniature acetone gas sensors.

In the present research, a new nanocomposite material of CuO-ZnO was prepared by Sol-gel method. The optimum gas sensing properties to acetone were obtained by 4.17% CuO-ZnO nanocomposites at about 30ºC operating temperature when it was irradiated by visible light with the wavelength more than 420 nm.

The purpose of this study is to synthesize a semiconductor photocatalyst which responds to both UV light and visible light in removal of organic dyes.

ZnO nanoparticles were pre-synthesised via sol-gel method using zinc nitrate tetrahydrate and methanamine at 90°C for 20 h. Subsequently, the as-synthesised ZnO nanoparticles were filtered, washed and dried. To synthesize ZnO-MnO₂ core shell nanocomposites (CSNs), 2:3 M ratio of KMnO₄ and MnSO₄ solution was stirred for an hour. Next, ZnO nanoparticles were added into the solution. The solution was heated at 160°C for 3 h for the formation of ZnO-MnO₂ CSNs. The structural, optical and photocatalytic properties of ZnO-MnO₂ CSNs were characterised by field emission scanning electron microscope, transmission electron microscopy (TEM), X-ray diffractometer and PL spectroscopy, respectively.

The photodegradation efficiencies of rhodamine B (RhB) dye by ZnO-MnO₂ CSNs as photocatalysts are 87.1 per cent under UV irradiation and 76.6 per cent under visible light irradiation, respectively. Their corresponding rate constants are 0.016 min⁻¹ under UV irradiation and 0.013 min⁻¹ under visible light irradiation. It can be concluded that N-deethylation was the dominant step during the photodegradation of RhB dye as compared to cycloreversion. The ZnO-MnO₂ CSNs demonstrated good photostability after three consecutive runs.

ZnO-MnO₂ CSN photocatalyst which could response to UV and visible light in degradation of RhB dye was synthesised using sol-gel method. The analysis shows that N-deethylation was the key photodegradation mechanism of RhB by ZnO-MnO₂ CSN.

The textile sector is moving towards new technologies, where the application of nanotechnology is offering fabrics with multifunctional properties making fabric odourless, hydrophobic, durable and self-cleaning. This aim of this research is to investigate self-cleaning ability of denim fabric with the application of zinc oxide nanoparticles (ZnO NPs) synthesized naturally. The primary focus of this investigation is achieving sustainability mark through green synthesis of ZnO NPs.

In this analysis, ZnO NPs being one of the metal oxides exhibiting self-cleaning, UV-protective and anti-microbial properties were synthesized naturally using Azadirachta Indica leaves. The prepared NPs were characterized by using X-ray diffraction and scanning electron microscopy analyses confirming their size and crystalline structure. Different formulations were investigated with varying concentration of zinc oxide and auxiliaries onto the denim fabric using pad-dry-cure application technique.

XRD analysis confirmed the successful green synthesis of ZnO NPs. SEM analysis revealed the homogeneous and hexagonal wurtzite NPs deposition on the denim fabric. It was ascertained that with 5% ZnO NPs and 7% Binder concentrations, the formulation resulted in a smooth and even layer on the denim fabric maintaining the appearance and feel at the same time offers appreciable grading (Grade 4) against the stringent stains of Ketchup, Coffee, Grape and Orange Juice with insignificant change in tensile strength.

In this study, self-cleaning attributes of denim fabric with zinc oxide nano formulations of different composition was studied to achieve promising functional properties in a single step not studied earlier.

Staphylococcus aureus (S. aureus), Klebsiella pneumoniae (K. pneumoniae) and Streptococcus pneumoniae (S. pneumoniae) are among the pathogens detected during Hajj pilgrimage known to cause pneumonia. This study aims to evaluate the antibacterial activity of activated carbon cloth (ACC) with Ag⁺ impregnated with zinc oxide nanoparticles (ZnO NPs) against these pathogens.

ZnO NPs were impregnated into ACC-Ag⁺ via layer-by-layer (LbL) self-assembly. Scanning electron microscope (SEM) was used to observe the fine surface morphological details of the ACC-Ag⁺-ZnO sheets. Antibacterial activity of the ACC-Ag⁺-ZnO sheets was evaluated using the disk-diffusion susceptibility assay. Allergy patch test was done to evaluate allergic reactions of the ACC-Ag⁺-ZnO sheets on human skin.

SEM micrographs showed successful impregnation of ZnO NPs into the ACC-Ag⁺ sheets. Disk-diffusion susceptibility assay results of ACC-Ag⁺-ZnO sheets against S. aureus, K. pneumoniae and S. pneumoniae showed good antibacterial activity; with 1.82 ± 0.13 mm zone of inhibition for S. pneumoniae, at a ZnO concentration of 0.78 mg mL^-1. No signs of human skin irritation were observed throughout the allergy patch test.

Results indicate that ACC-Ag⁺-ZnO sheets could potentially be embedded within surgical face masks (pilgrims’ preferred) to reduce the risks involved with the transmission of respiratory tract infections during and after mass gatherings (e.g. Hajj/Umrah, Olympics).