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This study explores the potential corrosion inhibition mechanisms of alkanolammonium salts, exemplified by ethylethanolammonium 4-nitrobenzoate (EEA4NB), for carbon steel, utilizing experimental and theoretical methods. The interactions between metal and inhibitor, focusing on adsorption behavior in saline solutions, will be thoroughly investigated. Analysis of potentiodynamic polarization curves and electrochemical impedance spectroscopy reveals that the inhibition efficiency (IE) increases with the rising concentration of EEA4NB, reaching 96% at 5 × 10−3 M. Negative adsorption free energy and a high adsorption equilibrium constant suggest the spontaneous formation of a protective inhibitor layer on the metal surface, effectively blocking reaction sites and reducing the corrosion rate, according to the Langmuir isotherms model. As confirmed by scanning electron microscopy, physical and chemical interactions contribute to the adsorption mechanisms. Quantum chemical calculations explore the relationship between EEA4NB molecular configuration and inhibition efficiencies. The study emphasizes the potential efficacy of alkanolammonium salts, exemplified by EEA4NB, as effective corrosion inhibitors for carbon steel in aggressive environments.

Lithium-ion polymer batteries, also known as lithium-polymer, abbreviated Li-po, are one of the main research topics nowadays in the field of energy storage. This review focuses on the use of the phosphorus containing compounds in Li-po batteries, such as polyphosphonates and polyphosphazenes. Li-po batteries are mini-devices, capable of providing power for any portable gadget. From a constructive point of view, Li-po batteries contain an anode (carbon), a cathode (metal oxide), and a polymer electrolyte, which could be liquid electrolytes or solid electrolytes. In general, a divider is used to keep the anode and cathode from touching each other directly. Since liquid electrolytes have a generally high ionic conductivity, they are frequently employed in Li-ion batteries. In the last decade, the research in this field has also focused on solving safety issues, such as the leakage of electrolytes and risk of ignition due to volatile and flammable organic solvents. The research topics in the field of Li-po remain focused on solving safety problems and improving performance.

Coordination polymer (CP)-type adsorbents impregnated with ionic liquids that are used to remove phenol from wastewater must be regenerated. A simple washing of the adsorbent releases about 70% from the spent adsorbent. In order to increase and study the phenol release, an electrochemical method was used. For this purpose, an electrochemical commercial graphite electrode was used as the working electrode, and the electrolyte support was a 3% NaCl solution. During the electrochemical investigation, the spent CP was immersed in a saline solution. The PH content in the electrolyte affected the direct electrooxidation (EO); the formation of BQ appeared to be accelerated by a lower concentration and a slower release of PH. After 90 min, an efficiency of PH electrooxidation (EOPH) of 36.22% from Cu-PA and EOPH of 42.14% from Cu-PA-IL, respectively, was achieved. These results were significantly higher than the EOPH of the solution resulting from washing the wasted adsorbent with a saline solution (22.58%). This work highlights the potential for the simultaneous electrooxidation of desorbed PH and the recovery of spent adsorbent in this situation. The number of cycles in which the adsorbent can be used without losing its absorbance ability is three.

Polyester coatings containing metal-organic framework (MOF) corrosion inhibitors were studied for their ability to protect carbon steel. The polyester coating was synthesized in the laboratory using microwave (MW) radiation to polycondense soy fatty acids, phthalic anhydride, and pentaerythritol-type polyols. The incorporation of these inhibitors into the polyester coating altered the behavior of the carbon steel, resulting in enhanced corrosion protection compared with uncoated carbon steel and polyester alone. Polyester with a 49% oil content, prepared using fatty acids from soybeans, phthalic anhydride, and pentaerythritol synthesized under microwave irradiation, and with a content of 3 mM Mg(GLY), exhibited a notable enhancement in the anticorrosive properties of the alkyd coating. The inhibition mechanism of corrosion was investigated through electrochemical impedance spectroscopy analysis.

Carbonyl olefinations are among the most important organic syntheses that form C=C bonds, as they usually have high yields and in addition offer excellent stereoselectivity. Due to these advantages, carbonyl olefinations have important pharmaceutical and industrial applications. These reactions contain an additional step of an α-functionalized carbanion to an aldehyde or ketone to produce alkenes, but syntheses performed using metal carbene complexes are also known. The Wittig reaction is an example of carbonyl olefination, one of the best ways to synthesize alkenes. This involves the chemical reaction between an aldehyde or ketone with a so-called Wittig reagent, for instance phosphonium ylide. Triphenylphosphine-derived ylides and trialkylphosphine-derived ylides are the most common phosphorous compounds used as Wittig reagents. The Wittig reaction is commonly involved in the synthesis of novel anti-cancer and anti-viral compounds. In recent decades, the use of ultrasound on the Wittig reaction (and on different modified Wittig syntheses, such as the Wittig–Horner reaction or the aza-Wittig method) has been studied as a green synthesis. In addition to the advantage of green synthesis, the use of ultrasounds in general also improved the yield and reduced the reaction time. All of these chemical syntheses conducted under ultrasound will be described further in the present review.

The inhibition effect of N,N′-phosphonomethylglycine (PMG) and vinyl phosphonic acid (VPA) on the 3% NaCl acidic solution corrosion of carbon steel iron was studied at different immersion times by potentiodynamic polarization, electrochemical impedance spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and computational methods. It is found from the polarization studies that PMG and VPA behave as mixed-type inhibitors in NaCl. Values of charge transfer resistance (Rct) and double layer capacitance (Cdl) in the absence and presence of inhibitors are determined. The PMG and VPA inhibitors were capable of inhibiting the corrosion process up to ≈91% and ≈85%, respectively. In the presence of PMG, the synergic effect of chlorine ions was observed. Density functional theory (DFT) was engaged to establish the adsorption site of PMG, VPA, and their deprotonated states. For studied compounds, the resulted values of ELUMO, EHOMO, energy gap (∆E), dipole moment (μ), electronic hardness (η), global softness (σ), electrophilic index (ω), and the electronic potential map are in concordance with the experimental data results regarding their corrosion inhibition behavior and adsorption on the metal surface.

Metalloporphyrins are highly recognized for their capacity to act as sensitive substances used in formulation of optical, fluorescent, and electrochemical sensors. A novel compound, namely Pt(II)-5,10,15,20-tetra-(4-allyloxy-phenyl) porphyrin, was synthesized by metalation with PtCl2(PhCN)2 of the corresponding porphyrin base and was fully characterized by UV-vis, fluorimetry, FT-IR, 1H-NMR, and 13C-NMR methods. The fluorescence response of this Pt-porphyrin in the presence of different concentrations of hydrogen peroxide was investigated. Besides, modified glassy carbon electrodes with this Pt-porphyrin (Pt-Porf-GCE) were realized and several electrochemical characterizations were comparatively performed with bare glassy carbon electrodes (GCE), in the absence or presence of hydrogen peroxide. The Pt-porphyrin demonstrated to be a successful sensitive material for the detection of hydrogen peroxide both by fluorimetric method in a concentration range relevant for biological samples (1.05–3.9 × 10−7 M) and by electrochemical method, in a larger concentration range from 1 × 10−6 M to 5 × 10−5 M. Based on different methods, this Pt-porphyrin can cover detection in diverse fields, from medical tests to food and agricultural monitoring, proving high accuracy (correlation coefficients over 99%) in both fluorimetric and electrochemical measurements.

The aim of the present work was the study of phosphonic acids grafting on the surface of SnO2 at different molar ratios. In this paper we describe the functionalization of SnO2 surfaces with phosphonic acids RPO(OH)2. The surface modification process was achieved by using phenyl-phosphonic acid (PPA) and vinyl-phosphonic acid (VPA). The synthesized materials were investigated by using FT-IR, TGA (in air and in nitrogen), EDX, ESEM, and TEM methods. This synthetic approach has many advantages: films with optical quality and controlled thickness can be obtained using low temperatures and cheap raw materials, by using “green chemistry” synthetic routes. The hybrid materials have structures diversity and fascinating applications, attracting attention for a long time, due to their potential.

One well-known method for hybrids synthesis with incorporated organic dyes is sol-gel method, which is based on the concept of molecular manipulation to design ceramics, glasses, and composites. The low-temperature process allows for the incorporation of guest organic molecules within the inorganic matrix, as well as for the synthesis of hybrid networks in which the organic and inorganic phases are interpenetrating. The aim of the work presented in this paper was the preparation of the gels with three different dyes, at different molar ratios by using the hydrolytic sol-gel process. The interaction of the dye and the oxide was examined by UV-vis spectroscopy and FT-IR. The thermal stability of the hybrid organic-inorganic xerogel formed here was studied by thermal analysis. The micrographs obtained by scanning electron microscopy (SEM) revealed the high density of the films. Such characteristics indicate the possible application of these films in solar cells.

Bromide ions are present in many environments, such as sedative drugs, methyl-bromide-treated vegetables and seawater. Excess bromide in humans interferes with iodide metabolism and is considered toxic. The need for fast and inexpensive methods for bromide detection is of interest. Spectrophotometric detection methods provide accurate and sensitive results. The well-known ability of metalloporphyrins to bind anionic ligands to the central metal ion has been exploited. The changes in the optical properties of Pt(II) 5,10,15,20-tetra(4-methoxy-phenyl)-porphyrin (PtTMeOPP) under the influence of bromide ions allowed us to achieve a fast, simple and reliable UV-vis spectrophotometric method of detection with a detection limit of 2.5 × 10−8 M and a good confidence coefficient: 99.05%. The potential interfering ions, such as Cl−, I−, NO2−, NO3−, SCN−, SO32−, SO42− and PO43− of 100-fold higher and Cl− and R-S− of 1000-fold higher concentrations in the mixture as compared to the determined concentration of bromide ions (c = 10−5 M), were tested and did not influence the results. The behavior of the sensitive porphyrin in various pH media was investigated in order to determine their influence upon the bromide detection capacity.

This paper is directed towards the development of safe, and thermally stable solid polymer electrolytes. Linear phosphorus-containing (co)polyesters are described, including their synthesis, thermal analysis, conductivity, and non-flammability. Polycondensation of phenylphosphonic dichloride (PPD) with poly(ethylene glycol) (PEG 12000) with and without bisphenol A (BA) was carried out using solid-liquid phase transfer catalysis. Potassium phosphate is used as base. Yields in the range of 85.0–88.0%, and inherent viscosities in the range of 0.32–0.58 dL/g were obtained. The polymers were characterized by gel permeation chromatography, FT-IR, 1H- and 31P-NMR spectroscopy and thermal analysis. Their flammability was investigated by measuring limiting oxygen index values. The polymers are flame retardants and begin to lose weight in the 190 °C–231 °C range. Solid phosphorus- containing (co)polyesters were complexed with lithium triflate and the resulting ionic conductivity was determined. Conductivities in the range of 10−7–10−8 S cm−1 were obtained.

Pt(II) 5,10,15,20-tetra(4-methoxy-phenyl)-porphyrin (PtTMeOPP) was used in the construction of new ion-selective sensors. The potentiometric response characteristics (slope and selectivity) of iodide and bromide-selective electrodes based on (PtTMeOPP) metalloporphyrin in o-nitrophenyloctylether (NPOE), dioctylphtalate (DOP) and dioctylsebacate (DOS) plasticized poly(vinyl chloride) membranes are compared. The best results were obtained for the membranes plasticized with DOP and NPOE. The sensors have linear responses with near-Nernstian slopes toward bromide and iodide ions and good selectivity. The membrane plasticized with NPOE was electrochemically characterized using the EIS method to determine its water absorption and the diffusion coefficient into the membrane.

The chemical polymerization of aniline was performed in phenylphosphinic acid (APP) medium using ammonium peroxidisulfate as the oxidizing agent, at 0 ºC and 25 ºC. The yield of polyaniline (PANI) was about 60–69 %. The polymerization process required an induction time 8–10 times greater than in other acids (hydrochloric, sulfuric). The average density of the obtained polymer was 1.395 g cm-3 for PANI-salt and 1.203 g cm-3 for PANI-base. The acid capacity of PANI depends on the synthesis parameters and the maximum value was 15.02 meq/g polymer. The inherent viscosity of PANI was 0.662 dl/g at aniline/oxidant molar ratios >2 and 0 ºC. The oxidation state was a function of the synthesis parameters and lay between 0.553–0.625, as determined from UV-VIS and titration with TiCl3 data. The PANI samples were characterized by measurements of their density, inherent viscosity, conductivity, acid capacity, FTIR and UV-VIS spectrum, and thermogravimetric data.

The use of graphene (Gr) and its derivates graphene oxide (GO) showed that these materials are good candidates to enhance the properties of polyurethane (PU) coatings, especially the anticorrosion ones since graphene absorbs most of the light and provides hydrophobicity for repelling water. An important aspect of these multifunctional materials is that all these improvements can be realized even at very low filler loadings in the polymer matrix. In this work, an ultrasound cavitation technique was used for the proper dispersion of GO nanosheets (GON) in polyurethane (PU) resin to obtain a composite coating to protect the AlMg3 substrate. The addition of GON considerably improved the physical properties of coatings, as demonstrated by electrochemical impedance spectroscopy (EIS) analysis, promising improved anticorrosion performance after accelerated UV-ageing. Computational methods and Differential Scanning Calorimetry (DSC) measurements showed that GON facilitates the formation of additional bonds and stabilizes the PU structures during the ultraviolet (UV) exposure and aggressive attack of corrosive species. Limiting oxygen index (LOI) data reveal a slow burning behaviour of PU-GON coatings during UV exposure, which is better than PU alone.