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This paper aims to investigate the potential of sol-gel coating as replacement for hazardous hexavalent chrome passivation treatment for galvanised iron (GI) sheet. Generally, corrosion resistance properties of the GI sheet are increased by hexavalent chrome passivation treatment. But hexavalent chrome is hazardous and not environment friendly.

The aim of this study was to understand the effect of nano zinc oxide (ZnO) on corrosion behaviour of sol-gel coating prepared by hydrolysis of the 3-(Glycidoxy propyl) methyl diethoxy silane (GPTMS) and tetra-ethyl-orthosilicate (TEOS). The morphology of the film was characterised by a scanning electron microscope (SEM). The corrosion resistance of the coated samples was evaluated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarisation curve and salt spray test.

From a different corrosion resistance study, it has been observed that sol-gel coating doped with 1 per cent nano ZnO rendered maximum corrosion protection. Beyond 1 per cent of nano ZnO, corrosion resistance property of coated galvanised steel sheet decreased drastically which may be due to agglomeration of nano ZnO and high water permeability of coated galvanised steel sheet.

The anti-corrosive property of the coating can be tested by means of atmospheric exposure which produces a real-time evaluation of the anti-corrosive nature of the coating under natural conditions rather than using an accelerated laboratory test.

It may be useful for other metal industry like aluminium. The work can be used as a guiding chemistry for development of chrome-free passivation for aluminium.

It has the potential to replace hexavalent chrome passivation.

The use of nano ZnO in sol-gel polymer matrix for the development of corrosion resistant chrome-free polymer coating for galvanised steel sheet and its corrosion resistance study (EIS curve fitting, capacitance value and water permeability) is a novel approach in this research.

The purpose of this paper is to introduce the simple synthesis process of thermal-insulation coating by using three different nanoparticles, namely, nano-zinc oxide (ZnO), nano-tin dioxide (SnO₂) and nano-titanium dioxide (TiO₂), which can reduce the temperature of solar cells.

The thermal-insulation coating is designed using sol-gel process. The aminopropyltriethoxysilane/methyltrimethoxysilane binder system improves the cross-linking between the hydroxyl groups, -OH of nanoparticles. The isopropyl alcohol is used as a solvent medium. The fabrication method is a dip-coating method.

The prepared S1B1 coating (20 Wt.% of SnO₂) exhibits high transparency and great thermal insulation property where the surface temperature of solar cells has been reduced by 13°C under 1,000 W/m² irradiation after 1 h. Meanwhile, the Z1B2 coating (20 Wt.% of ZnO) reduced the temperature of solar cells by 7°C. On the other hand, the embedded nanoparticles have improved the fill factor of solar cells by 0.2 or 33.33%.

Findings provide a significant method for the development of thermal-insulation coating by a simple synthesis process and low-cost materials.

The thermal-insulation coating is proposed to prevent exterior heat energy to the inside solar panel glass. At the same time, it can prevent excessive heating on the solar cell’s surface, later improves the efficiency of solar cell.

This study presents a the novel method to develop and compare the thermal-insulation coating by using various nanoparticles, namely, nano-TiO₂, nano-SnO₂ and nano-ZnO at different weight percentage.

Nanoparticles as the grease additives play an important role in anti-wear and friction-reducing property during the mechanical operation. To improve the lubrication action of grease, the tribological behavior of lithium-based greases with single (nanometer Al₂O₃ or nanometer ZnO) and composite additives (Al₂O₃–ZnO nanoparticles) were investigated in this paper.

The morphology and microstructure of nanoparticles were characterized by means of transmission electron microscope and X-ray diffraction. Tribological properties of different nanoparticles as additives in lithium-based greases were evaluated using a universal friction and wear testing machine. In addition, the friction coefficient (COF) and wear scar diameter were analyzed. The surface morphology and element overlay of the worn steel surface were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), respectively.

The results show that the greases with nanometer Al₂O₃ or nanometer ZnO and the composite nanoparticles additives both exhibit lower COFs and wear scar diameters than those of base grease. And the grease with Al₂O₃–ZnO composite nanoparticles possesses much lower COF and shows much better wear resistance than greases with single additives. When the additives contents are 0.4 Wt.% Al₂O₃ and 0.6 Wt.% ZnO, the composite nanoparticles-based grease exhibits the lowest mean COF (0.04) and wear scar diameter (0.65 mm), which is about 160% and 28% lower than those of base grease, respectively.

The main innovative thought of this work lies in dealing with the grease using single or composite nanoparticles. And through a serial contrast experiments, the anti-wear and friction-reducing property with different nanoparticles additives in lithium grease are evaluated.

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 paper aims to investigate the drying effect exhibited by pigments combined with a Co(II) salt of 2‐ethylhexanoic acid (Co(II)) in an alkyd resin modified by soya bean oil.

Paint hardening was studied by means of a method that follows the progress of alkyd film drying. Another important method was employed to monitor the gradually increasing hardness of the drying films. Hardness of thin films was measured by the Persos method. ZnO, ZnO nanoparticles, V₂O₅, ZnS and TiO₂ were used to study the effect of solid inorganic pigments on alkyd film drying. The pigment particles were characterised by scanning electron microscopy. The investigated pigments were combined with a constant amount of the Co(II) drier that acts in the system as a homogeneous catalyst, while the investigated pigments played the role of heterogeneous catalysts.

Using certain pigments as catalysts in drying, alkyd resins brings about new findings concerning the function of fillers and pigments in paint films. ZnO nanoparticles substantially accelerate film drying and moreover, the resulting films exhibit substantially higher hardness than films containing other inorganic pigments. To prepare films exhibiting higher hardness within a shorter time, one may also use ZnO microparticles or ZnS. TiO₂ and V₂O₅ were identified as pigments that either do not take part in the drying process or reduce the hardness of the resulting film.

The investigated catalytic system pigment/Co(II) drier can be advantageously used to accelerate the formation of alkyd paints modified by natural oils both for industrial and decorative purposes. It was established that hardness of paint films containing ZnO nanoparticles is twice as high as that of films containing only the Co(II) drier without any pigment. This finding makes new applications of alkyd paints possible in all instances where higher hardness is required.

Considering pigments as heterogeneous catalysts in systems producing films by the oxypolymerising mechanism is a new approach that gives rise to new and original solutions.

Nanoparticles of TiO₂ and ZnO were chemically synthesized by different routes and were characterized using Fourier transform infrared (FT-IR), Transmission electron microscopy (TEM), X ray diffraction (XRD) and Scanning electron microscopy (SEM). These particles were applied to cotton fabric using 1-10 wt% acrylic binder and cured. The photocatalytic activity of the finished fabric was investigated and a comparison was drawn between the synthesized and commercially available TiO₂ (Degussa P25) sample. Experiments were carried out by exposing the coffee stained samples to solar light. The self-cleaning leading to stain discolouration was quantified from the residual concentration of stain to assess the photoactivity of TiO₂ and ZnO nanoparticles. An attempt was also made to study the effect of concentration of nanoparticles (0.5-1.0 wt% on weight of fabric (owf) and acrylic binder concentration (1, 2, 10 wt% owf) on the self cleaning action. TiO₂ particles with smaller particle size of <10 nm was able to show significantly better activity than the commercial sample. At the same time, finish with nano ZnO though showed a bit lower activity; the self cleaning effect was significant and similar to the commercial TiO₂.

The purpose of this paper is to explore the effect of ZnO on the structure and properties of micro-arc oxidation (MAO) coating on rare earth magnesium alloy under large concentration gradient.

The macroscopic and microscopic morphology, thickness, surface roughness, chemical composition and structure of the coating were characterized by different characterization methods. The corrosion resistance of the film was studied by electrochemical and scanning Kelvin probe force microscopy. The results show that the addition of ZnO can significantly improve the compactness and corrosion resistance of the MAO coating, but the high concentration of ZnO will cause microcracks, which will reduce the corrosion resistance to a certain extent.

When the concentration of zinc oxide is 8 g/L, the compactness and corrosion resistance of the coating are the best, and the thickness of the coating is positively correlated with the concentration of ZnO.

Too high concentration of ZnO reduces the performance of MAO coating.

The MAO coating prepared by adding ZnO has good corrosion resistance. Combined with organic coatings, it can be applied in corrosive marine environments, such as ship parts and hulls. To a certain extent, it can reduce the economic loss caused by corrosion.

The effect of ZnO on the corrosion resistance of MAO coating in electrolyte solution was studied systematically, and the conclusion was new to the common knowledge.

This paper aims to investigation of processes for Pb²⁺ elimination from water/wastewater as a significant public health issue in many parts of world. The removal of Pb²⁺ ions by various nanocomposites has been explained from water/wastewaters. ZnO-based nanocomposites, as eco-friendly nanoparticles with unique physicochemical properties, have received increased attention to remove Pb²⁺ ions from water/wastewaters.

In this review, different ZnO-based nanocomposites were reviewed for their application in the removal of Pb²⁺ ions from the aqueous solution, typically for wastewater treatment using methodology, such as adsorption. This review focused on the ZnO-based nanocomposites for removing Pb²⁺ ions from water and wastewaters systems.

The ZnO-based nanocomposite was prepared by different methods, such as electrospinning, hydrothermal/alkali hydrothermal, direct precipitation and polymerization. Depending on the preparation method, various types of ZnO-based nanocomposites like ZnO-metal (Cu/ZnO, ZnO/ZnS, ZnO/Fe), ZnO-nonmetal (PVA/ZnO, Talc/ZnO) and ZnO-metal/nonmetal (ZnO/Na-Y zeolite) were obtained with different morphologies. The effects of operational parameters and adsorption mechanisms were discussed in the review.

The findings may be greatly useful in the application of the ZnO-based nanocomposite in the fields of organic and inorganic pollutants adsorption.

The present study is novel, because it investigated the morphological and structural properties of the synthesized ZnO-based nanocomposite using different methods and studied the capability of green-synthesized ZnO-based nanocomposite to remove Pb²⁺ ions as water contaminants.

The current review can be used for the development of environmental pollution control measures.

This paper reviews the rapidly developing field of nanocomposite technology.

This paper aims to present an analysis of several 3 D texture parameters for the entire wear scars obtained in severe regime, on a four-ball tester. The aim of this analysis is to correlate the tribological parameter as wear scar diameter to texture parameters.

Tested lubricants were rapeseed oil, rapeseed oil additivated with 1% Wt nano TiO₂ and rapeseed oil additivated with 1%Wt nano ZnO. The severe regime was applied for 1400 rpm and for loads increasing in steps of 50 N, from 500 to 900 N. Several analyzed roughness parameters (height parameters and functional ones) could be related to the evolution of a wear parameter, the wear scar diameter. Comparing the values for neat rapeseed oil and additivated variants, the texture parameters allow for evaluating if the additives protect or not the worn surfaces.

Measurements pointed out two groups of roughness parameters: one that has an evolution depending on wear scar diameter (WSD) and load (Sa, St, functional parameters) and one including Ssk that has shown no dependence on load and WSD. Also, the functional parameters Spk and Svk follow in a similar manner the wear parameter, WSD, but Sk is the least dependent on load. For the highest load, amplitude parameters such as Sa and St are following the tendency of WSD. Each lubricant has its particular correlation between wear parameters and texture quality, expressed by the help of a set of roughness parameters.

Such studies help tribologists to rank lubricants based on a combined analysis with wear parameters and texture parameters.

The results allow for evaluating new formulated lubricants.

The study on the quality on worn surfaces introduces the original idea of analyzing the entire wear scar surface (approximated by an ellipse with the axes as those experimentally measured) by the help of a set of 3 D roughness parameters.

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.