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The grafting of metal-bipyridine (Bpy-M, M = Mn or Zn) on aminopropyl-modified montmorillonite K10 (NH2-MK10) synthesized via a functionalization-immobilization-metalation route was investigated. Formulated NH2-MK10-Bpy-Mn and NH2-MK10-Bpy-Zn were characterized using BET, FTIR, SEM, XRD, CHNS and NH3-TPD techniques and tested for the synthesis of butyl acetoacetate (BAT) via the transesterification of ß-keto ethyl acetoacetate (EAA) with butanol (BTL). The influence of reaction parameters on the BAT yield was investigated using the Taguchi optimization approach. According to characterization data, the samples were mesoporous materials with a considerable number of acidic sites and diverse inorganic and organic functional groups, making them inorganic-organic hybrid catalysts. Optimization results showed that catalyst loading had the most significant impact on the BAT yield, followed by the BTL : EAA molar ratio and temperature, whereas the conversion time had the least impact on the reaction process. NH2-MK10-Bpy-Mn outperformed NH2-MK10-Bpy-Zn in the transesterification of ß-keto EAA, achieving 96.1 ± 0.79% conversion compared to 87.3 ± 0.94% at 110 °C for 7 h with a BTL : EAA molar ratio of 1.4 : 1 and catalyst loading of 2.0 wt%. Both catalysts were reusable and maintained good stability, which indicate their great potential for catalyzing the transesterification of ß-keto ester.

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Keeping recruitment of green and cost-effective solutions for environmental challenges in view, the current work was designed to solve the problems related to metal corrosion in the aqueous phases of crude oil in chemical industries. Green materials can play an important role in protecting metals from this corrosion. Hence, the green anti-corrosion material based upon gossypol derivate is suggested to solve the above problems. The electrochemical characteristics were appraised by cyclic voltammetry, electrochemical impedance spectroscopy, potentiodynamic polarization, and electrochemical noise methods. The thermodynamics were studied by gravimetric analyses. The surface morphology was scrutinized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Density functional theory and molecular dynamic simulations were exploited in theoretical analyses. The gossypol derivate is green, non-toxic, more efficient, non-volatile, and chemically stable anti-corrosion material for gas and oil industries. Carbon steel corrosion simulated in aqueous phases of crude oil (NaCl solutions (1.0 M) saturated with H2S and CO2) was maximally prohibited by forming a protective layer of binaphthalene. Its protection degree is 96.71% (at 100.0 mg/L/0.107 mM). The gossypol ring is a suitable core for preparing the next modification materials to protect against corrosion. The rigid adsorption progressed mainly via hydroxyl functional moieties. Compared to the inhibition behavior of the neutral form of gossypol, the optimized protonated form causes a greater inhibition.

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On a global scale, cancer is a difficult and devastating illness. Several problems with current chemotherapies include cytotoxicity, lack of selectivity, stem-like cell growth, and multi-drug resistance. The most appropriate nanomaterials for cancer treatment are those with characteristics, such as cytotoxicity, restricted specificity, and drug capacity and bioavailability; these materials are nanosized (1-100 nm). Nanodrugs are rarely licenced for therapeutic use despite growing research. These compounds need nanocarrier-targeted drug delivery experiments to improve their translation. This review describes new nanomaterials reported in the literature, impediments to their clinical studies, and their beneficial cancer therapeutic use. It also suggests ways to use nanomaterials in cancer therapy more efficiently and describes the intrinsic challenges of cancer treatment and the different nanocarriers and chemicals that can be utilised for specified tumour targeting. Furthermore, it provides a concise overview of cancer theranostics methods, with a focus on those that make use of nanomaterials. Although nanotechnology offers a great source for future advancements in cancer detection and therapy, there is an emerging need for more studies to address the present barriers to clinical translation.

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Two novel chitosan derivatives (water soluble and acid soluble) modified with thiocarbohydrazide were produced by a quick and easy technique using formaldehyde as links. The novel compounds were synthesized and then characterized by thermogravimetric analysis, elemental analysis, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and differential scanning calorimetry. Their surface morphologies were examined using scanning electron microscopy. These chitosan derivatives could produce pH-dependent gels. The behavior of mild steel in 5 % acetic acid, including both inhibitors at various concentrations, was investigated using gravimetric and electrochemical experiments. According to the early findings, both compounds (TCFACN and TCFWCN) functioned as mixed-type metal corrosion inhibitors. Both inhibitors showed their best corrosion inhibition efficiency at 80 mg L-1. TCFACN and TCFWCN, showed approximately 92 % and 94 % corrosion inhibition, respectively, at an optimal concentration of 80 mg L-1, according to electrochemical analysis. In the corrosion test, the water contact angle of the polished MS sample at 87.90 °C was reduced to 51 °C. The water contact angles for MS inhibited by TCFACN and TCFWCN in the same electrolyte were greater, measuring 78.10 °C and 93.10 °C, respectively. The theoretical results also support the experimental findings.

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A novel application of the Pistacia integerrima gall extract as an environmentally friendly corrosion inhibitor is reported in this study. The major phytochemicals present in the gall extract, namely pistagremic acid, ß-sitosterol, pistiphloroglucinyl ether, pistaciaphenyl ester, naringenin, and 5,7-dihydroxy-2-(4-hydroxyphenyl)-2,3-dihydrochromen-4-one, play key roles in its anticorrosive behavior on steel in aggressive media. Several approaches were used to study the corrosion prevention activity of steel in 1 M H2SO4, including weight loss analysis, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and density functional theory (DFT). At 2000 mg L-1, the highest efficiency of 92.19% was observed in 1 M H2SO4. An SEM study was conducted to validate the surface coverage of the metal surface. DFT studies revealed several nucleophilic regions present in the phytochemicals of the inhibitor, which supported the favorable nucleophilicity. Corrosion studies have not been performed on this sample. Phytochemicals make it an effective corrosion inhibitor, and its extraction process utilizes distilled water, making it better than other inhibitors. It has been proven that the obtained values of ΔEInhDFT for pistiphloroglucinyl, pistaciaphenyl ether, and naringenin organic compounds were very low, confirming the high reactivity of these corrosion inhibitors. The order of the values of ΔEInhDFT is as follows: pistaciaphenyl ether > pistiphloroglucinyl ether > naringenin organic compound; this suggests that pistaciaphenyl ether is more reactive than the other compounds. In this study, P. integerrima gall extract emerges as a novel and highly effective corrosion resistance agent in 1 M H2SO4, chosen for its relevance to acid pickling and cleaning processes.

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Corrosion is a pervasive issue with significant economic and safety implications across various industries. Nanoceramic-based coatings have emerged as a promising solution for corrosion protection due to their unique properties and mechanisms. This review aims to comprehensively examine the synthesis, mechanisms, and applications of nanoceramic-based coatings for corrosion protection. The review begins by highlighting the importance of corrosion protection and its impact on different industries. It introduces nanoceramic-based coatings as a potential solution to address this challenge. The objective is to provide a thorough understanding of the synthesis methods, mechanisms, and applications of these coatings. The fundamental principles of corrosion and different corrosion mechanisms are discussed, along with the limitations of traditional corrosion protection methods. The review emphasizes how nanoceramic-based coatings can overcome these limitations and provide superior corrosion resistance. Various synthesis methods, including sol-gel, electrodeposition, and physical vapor deposition, are described in detail, along with the factors influencing the synthesis process. Recent advancements and innovations in nanoceramic coating synthesis techniques are also highlighted. This looks at how coatings made with tiny ceramic particles protect against corrosion. It examines the importance of small-scale details like particle size, shape, and what the particles are made of. The formation of passive layers, self-healing mechanisms, and barrier properties of nanoceramic coatings are explained. The diverse applications of nanoceramic coatings for corrosion protection in industries such as automotive, aerospace, and marine are comprehensively discussed. Case studies and examples demonstrating the significant corrosion resistance and improved performance achieved with nanoceramic coatings are presented.

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The corrosion of carbon steel infrastructure in acidic environments poses significant economic and safety challenges. Traditional inhibitors such as chromates are being phased out due to toxicity concerns. Thus, there is a need to develop effective and sustainable green alternatives. In this work, we evaluated an epoxy-based inhibitor, bisphenol A tetrabromo dipropoxy dianiline tetraglycidyl ether (TGEDADPTBBA), for protecting carbon steel against corrosion in 1 M hydrochloric acid. An integrated experiment-computation approach was employed. Polarization curves and electrochemical impedance spectroscopy were used to assess the inhibition efficiency and mechanism of TGEDADPTBBA. Quantum chemical calculations and molecular dynamics simulations provided atomic-level insights into adsorption behavior. Scanning electron microscopy with energy-dispersive X-ray spectroscopy characterized the surface morphology. The results showed that TGEDADPTBBA acted as a highly effective mixed-type inhibitor, achieving over 95% inhibition efficiency at a 10-3 M concentration. It suppressed corrosion currents while increasing the charge transfer resistance. Theoretical studies revealed that TGEDADPTBBA adsorbed onto steel surfaces via both electrostatic and van der Waals interactions. This stable adsorption facilitated the formation of a protective barrier layer, as observed experimentally. Notably, our work demonstrated the synergistic potential of combining experimental corrosion testing with computational modeling to develop structure-property relationships for innovative inhibitor design. This integrated approach offers insight into inhibition mechanisms and presents TGEDADPTBBA as an attractive green corrosion inhibitor alternative for industrial applications.

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It is well known that metal corrosion causes serious economy losses worldwide. One of the most effective ways to prevent corrosion is the continuous development of high-efficient and environment-friendly corrosion inhibitors. Among the widely used organic and inorganic corrosion inhibitors, plant extracts are top candidates due to their nontoxic nature. The present study reports a novel application of the methanolic extract of Terminalia bellerica fruits as an environment friendly corrosion inhibitor for steel in sulphuric acid medium. The phytochemicals of the extract, namely Ellagic, Gallic, and Malic acids, play a key role of the anti-corrosive behavior of the extract. The corrosion prevention activity was studied on the steel in 1 M H2SO4 using a variety of approaches including weight loss analysis (WL), scanning electron microscope (SEM), electrochemical impedance spectroscopy (EIS), density functional theory (DFT), natural bond orbital analysis (NBO), Fukui function and Monte Carlo simulations (MC). In 1 M H2SO4 solution, the maximum electrochemical inhibition efficiency of 91.79% was observed at 4000 mg/L concentration of the extract. The NBO analysis showed that the charge density of the double bonds and the oxygen atoms of carbonyl and hydroxyl groups of the phytochemicals lies on the top of the natural bond orbitals which promotes the anticorrosive properties of the investigated inhibitors. The surface coverage of steel was validated by SEM measurements. According to DFT studies, numerous nucleophilic regions were present in the active phytochemical constituents of the inhibitor, demonstrating their favorable nucleophilicity. The computed electronic structure of the phytochemicals revealed band gaps of 4.813, 5.444, and 7.562 eV for Ellagic, Gallic, and Malic acids respectively suggesting effective metal-inhibitor interactions. A good correlation between experimental and theoretical findings was addressed.

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Three novel natural amino acid-derived sodium L-2-(1-imidazolyl) alkanoic acids (IZSs), namely, sodium 2-(1H-imidazol-1-yl)-4-methylpentanoate (IZS-L), sodium 2-(1H-imidazol-1-yl)-3-phenylpropanoate (IZS-P), and sodium 2-(1H-imidazol-1-yl)-4-(methylthio)butanoate (IZS-M), were investigated as corrosion inhibitors. The IZSs were synthesized following the green chemistry principles, and their structure was characterized using FTIR and NMR techniques. The corrosion study results reveal that a moderate concentration of IZSs (having low solution conductivity) showed potential corrosion inhibition for mild steel in artificial seawater. At longer immersion, IZS-P forms a uniform protective film and exhibits the potential inhibition efficiency of 82.46% at 8.4 mmol L-1. Tafel polarization results reveal that IZS-P and IZS-M act as mixed types with an anodic predominantly corrosion inhibitor. The electrochemical impedance spectroscopy results signify that IZSs inhibit mild steel corrosion through the formation of an inhibitor film on the metal surface, which was further confirmed by the FTIR, SEM, EDX, and XPS studies. DFT result shows that in IZS-P, the benzylic group (-CH2-Ph) has greater electron distribution compared to isobutyl (-CH2CH(CH3)2) in IZS-L and methythioethyl group (-CH2CH2SCH3) which supported the corrosion inhibition performance at longer immersion [IZS-P (82.46%) > IZS-M (67.19%) > IZS-L (24.77%)].

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ß-Cyclodextrin-based compounds are used to develop and innovate materials that protect against corrosion due to their sustainability, low cost, environmental friendliness, excellent water solubility and high inhibition efficiency. However, corrosion potentials of ß-CD-based compounds were not reviewed with the modern trends. The essence of the problem is that a deep understanding of the development and innovation of ß-CD-based compounds as corrosion inhibitors is very important in creating next-generation materials for corrosion protection. In this review, the fundamental behaviour, importance, developments and innovations of ß-CD modified with natural and synthetic polymers, ß-CD grafted with the organic compounds, ß-CD-based supramolecular (host-guest) systems with organic molecules, polymer ß-CD-based supramolecular (host-guest) systems, ß-CD-based graphene oxide materials, ß-CD-based nanoparticle materials and ß-CD-based nanocarriers as corrosion inhibitors for various metals were reviewed and discussed with recent research works as examples. In addition, the corrosion inhibition of ß-CD-based compounds for biocorrosion, microbial corrosion and biofouling was reviewed. It was found that (i) these compounds are sustainable, inexpensive, environmentally friendly, and highly water-soluble and have high inhibition efficiency; (ii) the molecular structure of ß-CD makes it an excellent molecular container for corrosion inhibitors compounds; (iii) the ß-CD is excellent core to develop the next generation of corrosion inhibitors. It is recommended that (i) ß-CD compounds would be synthesized by green methods, such as using biological sustainable catalysts and green solvents, green methods include irradiation or heating, energy-efficient microwave irradiation, mechanochemical mixing, solid-state reactions, hydrothermal reactions and multicomponent reactions; (ii) this review will be helpful in creating, enhancing and innovating the next green and efficient materials for future corrosion protection in high-impact industries.

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N-doped carbon quantum dots (NCQDs) were synthesized by a hydrothermal method using folic acid and o-phenylenediamine as precursors. The inhibition behaviour of the NCQDs on Q235 steel in 1 M HCl solution was appraised through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves (PDP), and surface analysis. The results demonstrated that the synthesized NCQDs had an effective anticorrosion effect on Q235 steel, and the corrosion inhibition efficiency of 150 mg/L NCQDs reached 95.4%. Additionally, the analysis of the PDP corrosion potential changes indicated that the NCQDs acted as a mixed corrosion inhibitor. Moreover, the NCQDs adsorbed onto the surface of steel by coordinating its electron-rich atoms with the iron metal to form a protective film, which slowed the dissolution reaction of the anodic metal to achieve corrosion inhibition. The adsorption mechanism of the NCQDs was consistent with Langmuir adsorption, including physical and chemical adsorption. Therefore, this work can inspire and facilitate, to a certain extent, the future application of doped carbon quantum dots as efficient corrosion inhibitors in pickling solutions.

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