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This paper aims to prepare a composite film on LY12 aluminum (Al) alloy by immersing in dodecyl phosphate and cerium nitrate solution by self-assembling methods. The effect of dipping sequence in dodecyl phosphate and cerium nitrate solution on the corrosion resistance of the composite film is studied.

The corrosion resistance of the dodecyl phosphate/cerium composite film is investigated by electrochemical measurement and film composition analysis.

The dipping sequence in dodecyl phosphate and cerium nitrate solutions has a significant impact on the corrosion resistance of the composite film. It shows best corrosion resistance by first dipping in dodecyl phosphate and then dipping in cerium nitrate solution.

The research shown in this work lays a scientific basis of the film preparation for industrial applications in the future.

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.

The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including E_HOMO, E_LUMO and optimized geometrical structure, were assumed and discussed in detail.

The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as E_HOMO, E_LUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.

This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.

This paper aims to investigate the effect of cerium modification and electrodeposition on the properties of the silane films obtained. Besides, the influence of dissolved oxygen was also researched through inhalation of oxygen or nitrogen. Moreover, the corresponding corrosion behavior of the silane films was also studied.

In this paper, surface morphology and corrosion-resistant properties of the films were characterized by scanning electron microscopy, electrochemical impedance spectroscopy, immersion test and the salt spray test.

The paper reveals that all the practical parameters including the concentration of dissolved oxygen had a marked effect on the anti-corrosive performance of the films, which may be attributed to the dense and compact structure of the films obtained. Furthermore, the self-healing ability of the films had also been enhanced through the rise of dissolved oxygen concentration in proper proportion.

This paper reveals the effect of practical parameters on the properties of the silane films obtained and the corrosion behavior of these films.

The purpose of this paper is to develop hybrid organic‐inorganic silica‐based nanocomposite films, by sol‐gel method, for corrosion protection of AA2024 alloy. Also, cerium nitrate corrosion inhibitor is introduced into the optimized coating in the next step of the investigations in order to study the improvement in the corrosion protection properties of the organically modified silicate (Ormosil) films.

The sol‐gel films have been synthesized from 3‐glycidoxypropyltrimethoxysilane and tetraethylorthosilicate precursors. In order to investigate the effective factors on the properties of Ormosils films, different coatings with different organic and hydrolysis water content were developed. Then, cerium nitrate corrosion inhibitor was added to the coatings. The structure of the hybrid sol‐gel films was studied by scanning electron microscopy. The corrosion protection properties of the films were studied by potentiodynamic scanning, and electrochemical impedance spectroscopy, respectively.

The results indicate that the hybrid films provided exceptional barrier and corrosion protection in comparison with untreated aluminium alloy substrate. Moreover, improvement of the protection properties of the films containing cerium nitrate corrosion inhibitor occurred with immersion time. This would imply that cerium ions could reach the defects, and reduce the corrosion rate.

This paper provides the development of Ormosils coating, which exceptionally improves the corrosion protection of 2024 aluminium alloy.

The purpose of this paper is to develop a chrome-free and phosphorus-free chemical conversion coating with good corrosion resistance, a novel chemical conversion coating was prepared by adding cerium nitrate hexahydrate and salicylic acid in the treatment solution containing titanium/zirconium ions on 6061 aluminum alloy.

Compared with the AA6061 aluminum alloy matrix, the self-corrosion potential of the conversion coating is significantly positively shifted, the self-corrosion current density is greatly reduced and its corrosion resistance is significantly improved. Morphology and composition of the conversion coatings were observed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The microdomain structure of conversion coatings at different formation stages was analyzed by electron probe microanalyzer.

An optimized preparation technique of titanium–zirconium chemical conversion coating for AA6061 aluminum alloy is obtained: H₂TiF₆ 4 mL/L, H₂ZrF₆ 0.4 mL/L, salicylic acid 0.35 g/L, Ce(NO₃)₃·6H₂O 0.14 g/L, reaction temperature 30°C, reaction time 120 s and pH 4.0.

The coating forms on the Al(Fe)Si intermetallic compound, and Ce³⁺ is preferentially adsorbed on the intermetallic compound. The hydrolysis of Ce³⁺ causes the local pH of the solution to decrease, which promotes matrix dissolution and charge migration. As the microanode/microcathode reaction occurs, the local pH of the solution increases, and Al₂O₃/ZrO₂/TiO₂ begins to deposit on the surface of the metal substrate.

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.

In this Chapter, cerium (III) oxide nanoparticles were prepared by co-precipitation method using hydrogen peroxide as the precipitant in slightly alkaline medium which is greener and environmentally suitable, cheap and best as compared to other conventional methods. Here, hydrogen peroxide acts as precipitating, reducing and stabilizing agents. Since studies worldwide reveal a very strong, significant positive association between air pollution and COVID-19 cases, hence, this environment-friendly synthesis process will prove to be most economically effective one to combat the COVID situation. The synthesized cerium (III) oxide nanoparticles were initially noted through visual color change from colorless pale yellow cerium (III) to light yellow cerium (IV). Moreover, the formation and size of cerium (III) oxide nanoparticles were evidenced by the X-ray diffraction, transmission electron microscopy and UV-VIS spectroscopy studies. The very high surface area and very small average crystallite sizes of these prepared cerium (III) oxide nanoparticles (5–20) nm in size is mainly responsible for their catalytic properties and hence can be effectively used for the removal of hazardous toxic pollutant gases such as carbon dioxide and sulfur dioxide from the environment with a view to combat the pollution within the environment to increase sustainability and also ensure a better, healthy and safe environment, particularly, in context of COVID in globalized world. This chapter, as its main objective, mainly focuses on utility of the nanotechnology and its beneficiary in creating a sustainable environment in economic world, particularly for gender development. Since the gas sensors will detect and reduce gaseous toxic pollutants from the environment, so lower the pollution greater will be sustainable environment development in terms of human development index and hence higher will be overall economic development in favor of Gender Development Index across world. However, as major findings, developing countries have been successful in maintaining a sustainable human development, in spite of higher Per Capita Income (PCI) growth, as compared to the role of least developing countries, with lower PCI in this global world, in favor of their respective gender development.

The purpose of this paper was to prepare the cerium-based conversion coating on AZ91D magnesium alloy, and its compositions, micro-morphology, corrosion resistance and the chemical valence state of the film elements were investigated.

The methodology comprised preparation of coatings at different temperatures, which then were characterized using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, an electrochemistry workstation and by means of X-ray photoelectron spectroscopy.

The conversion coating had a micro-cracked morphology. The conversion coatings were composed of MgO (or Mg-OH), CeO₂ and Ce2O₃. The best corrosion resistance of the cerium passivation film appeared when the treatment temperature was about 35°C.

The corrosion current densities of conversion coatings were lower by one to two orders of magnitude than the corrosion current density of the blank sample. The rare earth passivation coating prepared under the best condition could reduce the corrosion current to 3.548 × 10−6 A/cm2.

The purpose of this paper is to study the compound effect between silane and cerium salts in the passivation process of chemical conversion treatment of zinc.

Chemical conversion treatment using 3‐Glycidoxypropyltrimethoxysilane on zinc is investigated as an alternative treatment to chromate conversion. The surface chemistry of the silane‐treated samples is investigated with mass change measurements, polarization curves, electrochemical impedance spectroscopy (EIS) and the salt spray tests (SST). The surface morphology of samples was studied using a scanning electron microscope.

The polarization curves, EIS and SST data are in agreement. On the surface of zinc, the silane formed a compound with the cerium, thus enhancing the adhesion and corrosion resistance of the polymer film.

There have been few reports on the compound effects of silanes and cerium salts in the passivation process. The mechanism of this compound effect may be due to the ability of Ce^3 +ions to gain access to the interface through tiny cracks or micropores in the cross‐linking structure of GPS polymer films on zinc, and the subsequent oxidation of Ce^3 +to Ce^4 +by H₂O₂ may result in a barrier effect between the electrolyte and the metallic substrate.