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Öğe Corrosion inhibition of reinforcement steel in mixture water by caffeine and L-arginine(Taylor & Francis Ltd, 2021) Kurtay, Mine; Gerengi, Husnu; Chidiebere, Arinzechukwu; Yildiz, MesutMany additives are preferred to extend the usage of concrete constructions in order to increase durability. These compounds have to be non-poisonous and have no undesirable consequences on the environs. Out of all these concerns, amino acids are mainly used in food and drug industries as well as safe corrosion inhibitors in a number of acid solutions. Here, the corrosion inhibition efficacy of optimum concentration (50 ppm) of caffeine and L-arginine has been investigated for reinforcement steel in mixture water (MW) environment. This was performed for a duration of 2 h, 7, 28, 56 and 90 d using electrochemical impedance spectroscopy (EIS), dynamic EIS (DEIS), and potentiodynamic polarization (PDP) techniques. The surface of specimens was also investigated by atomic force microscopy (AFM), optical profilometer (OP) and scanning electron microscopy (SEM). DEIS results indicate that selected inhibitors protected reinforcement steel approximately up to 62% against corrosion till 7 d, then the effectiveness of the protection decreased to 30% on 90th day. It was also observed that L-arginine showed better inhibition efficiency than caffeine.Öğe Investigation of Propolis as a Green Inhibitor of SAE 1010 Carbon Steel Corrosion in 3.5% NaCl Environment(Amer Chemical Soc, 2020) Rizvi, Marziya; Gerengi, Husnu; Yildiz, Mesut; Kekecoglu, Meral; Pehlivan, Mustafa MertThe anticorrosion performance of ethanolic extract of propolis (EEP) on SAE 1010 carbon steel specimens dipped in 3.5% NaCl was evaluated by advanced electrochemical and surface morphological assessments. The adsorption of EEP on the surface of the specimens investigated was delineated by an optical profilometer (OP), atomic force microscopy (AFM), and scanning electron microscopy (SEM) before and after immersion in aqueous solution of 3.5% NaCl. The electrochemical feedback assisted by PDP, EIS, and DEIS of the inhibited electrodes was compared with that of the uninhibited electrodes, and EEP's role in the formation of a protective barrier was identified. All the qualitative and quantitative data thus obtained establish EEP as a potential inhibitor for the SAE 1010 carbon steel corrosion in NaCl solution.Öğe Investigation on structural, optical, thermal, and dielectric properties of cellulose propionate/styrene-maleic anhydride copolymer/molybdenum nanocomposite prepared by pulsed laser ablation(Elsevier, 2024) Haladu, Shamsuddeen A.; Elsayed, Khaled A.; Ercan, Ismail; Ercan, Filiz; Kayed, T. S.; Demirci, Tuna; Yildiz, MesutPolymer nanocomposite films of cellulose propionate/styrene-maleic anhydride copolymer/molybdenum (CP/ SMAC/Mo) were fabricated by pulsed laser ablation of Mo in the polymer solution for 10, 20, and 30 min. The films were then characterized by various analytical methods. X-ray diffraction (XRD) revealed that the addition of Mo to CP/SMAC removed the crystalline peaks of Mo without changing the amorphous nature of the copolymer. According to the scanning electron microscopy (SEM) and atomic force microscopy (AFM) patterns, Mo atoms were trapped in the amorphous polymer stacks. The energy -dispersive X-ray (EDX) spectrum features C, O, and Mo. FTIR confirmed the embedding of Mo in the polymers. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were carried out on the samples. The pristine polymer film exhibited a band gap energy of 2.9 eV, which decreased to 2.05 eV because of the loading of the Mo nanoparticles. The intensity of the photoluminescence (PL) peak of the films increases with ablation time such that the absorption intensity of the film at a lambda max of 426 nm increases by trifold during the 30 min of irradiation, which is consequently due to the increased amount of Mo in the nanostructure. The incorporation of Mo in the polymer matrix enhances the dielectric constant ( epsilon') (6.28 -18.13) and ac conductivity ( sigma ac ) (3.19 x 10 - 5 -1.12 x 10 -4 S/cm) of the polymer with negligible dielectric loss. The results suggest possible technological utilization of these materials in such applications as supercapacitors, light -emitting diodes, and organic optoelectronic devices, among others.Öğe A newly synthesized ionic liquid as an effective corrosion inhibitor for carbon steel in HCl medium: A combined experimental and computational studies(Elsevier, 2021) Ozturk, Serkan; Gerengi, Husnu; Solomon, Moses M.; Gece, Gokhan; Yildirim, Ayhan; Yildiz, MesutSurfactants present exciting adsorption chemistry due to their dual nature, i.e the present of the hydrophobic and hydrophilic parts in their structures. However, the inhibition performance of surfactants is influenced by their chemical structure as well as the nature of the electrolyte. In acidic media, high concentration of tri-cationic surfactants is required for effective surface protection. Herein, we report the synthesis of a novel tri-cationic surfactant containing three quaternized nitrogen atoms and its corrosion inhibitive effect for carbon steel in 1 M aqueous HCl medium. The molecular structure of the surfactant was elucidated by 1H NMR and C-13 NMR spectroscopic techniques and its anti-corrosion activity was investigated by electrochemical impedance spectroscopy, potentiodynamic polarization and dynamic electrochemical impedance spectroscopy methods. The results obtained from the corrosion studies show that the synthesized surfactant is quite effective against the low carbon steel corrosion and at low inhibitor concentration. The inhibition efficiency obtained at 5 mg/L concentration is above 90%, showing that the anti-corrosion effect of the synthesized surfactant on the metal surface is strong even at low inhibitor concentration. Moreover, some physicochemical parameters namely, the critical micelle concentration, surface tension, micelle formation free energy, and emulsion stability have been calculated and used to explain the correlation with the corrosion inhibition mechanism. Additionally, to support the results from the electrochemical measurements, surface morphological examination using energy dispersive Xray spectroscopy (EDAX) and scanning electron microscope (SEM) methods have been performed. The EDAX and SEM results prove the adsorption of the tri-cationic surfactant molecule on the metal surface. The adsorption followed the Langmuir adsorption isotherm and calculated Kads (equilibrium constant of the adsorption process) value reflects strong interaction. More so, density functional theory (DFT) results corroborate the experimental results. The synthesized tri-cationic surfactant is a potential candidate for the formulation of acid corrosion inhibitor for acid cleaning applications.Öğe The potency of zeolite and diatomite on the corrosive destruction of reinforcing steel in 1 M HNO3 environment(Elsevier Sci Ltd, 2020) Kurtay, Mine; Gerengi, Husnu; Kocak, Yilmaz; Chidiebere, Maduabuchi A.; Yildiz, MesutConsidering the high neutralizing power of concrete, it is seen as the major material for preserving reinforcing steel. This is observed in reinforced concrete (RC) formation. It is obvious that under corrosive situations, concrete is subject to noticeable quality losses. The aim of this research is to conduct an inquiry on the disintegration of reinforcing steel subjected to 1 M HNO3 solution over 200 days. For this purpose, concrete samples were produced having three different formulations, which included the reference (pure Portland cement), 20% diatomite and 20% zeolite. Reinforcing steel was embedded into these concrete samples. Afterwards, the electrochemical impedance spectroscopy (EIS) approach was used to monitor the system every seven days. The results clearly revealed that long-term experiments are required for accurate electrochemical measurements. The addition of diatomite and zeolite protected the reinforcement better against corrosion. Although it loses its effectiveness over time, zeolite provided better resistance against corrosion than diatomite for the reinforcement bars in 1 M HNO3 solution. (C) 2019 Elsevier Ltd. All rights reserved.Öğe Shallow cryogenic treatment: effect on the corrosion resistance and hardness properties of AA5083-H111 alloy in chloride-ions enriched medium(Iop Publishing Ltd, 2021) Uz, Dogancan; Solomon, Moses M.; Gerengi, Husnu; Sahin, Mukerrem; Yildiz, MesutThe influence of cryogenic and cryogenic time (10, 24, 36, 48, and 72 h) on the hardness, surface roughness, and corrosion resistance properties of AA5083-H111 alloy in 3.5 wt.% NaCl solution have been investigated. The hardness property was analysed via the Brinell hardness measurement, the corrosion resistance property was measured electrochemically, while the morphological studies were undertaken using the SEM (scanning electron microscopy) and atomic force microscopy (AFM). The results disclose that the shallow cryogenic treatment at -80 degrees C improves the alloy's hardness, surface roughness, and the corrosion resistance. The best cryogenic treatment time is 24 h. Cryogenic treatment for 24 h increases the alloy's hardness from 71.3 HB to 74.90 HB, reduces the average surface roughness from 534.000 nm to 105.634 nm, and increases the total charge transfer resistance from 18139 omega cm(2) to 26230 omega cm(2). The improvement is linked to settling of fine particles on the alloy surface. The SEM results support these claims.Öğe Sodium nitrite as a corrosion inhibitor of copper in simulated cooling water(Nature Research, 2021) Rizvi, Marziya; Gerengi, Husnu; Kaya, Savas; Uygur, Ilyas; Yildiz, Mesut; Sarioglu, Ibrahim; El Ibrahimi, BrahimThe corrosion inhibition behavior of sodium nitrite (NaNO2) towards pure copper (99.95%) in simulated cooling water (SCW) was investigated by means of electrochemical impedance spectroscopy (EIS) and dynamic electrochemical impedance spectroscopy (DEIS). NaNO2 interferes with metal dissolution and reduce the corrosion rate through the formation or maintenance of inhibitive film on the metal surface. Surface morphologies illustrated that the surface homogeneity increased on adding sodium nitrite. Sodium nitrite's adsorption on copper surface followed the modified form of Langmuir, Freundlich and Frumkin isotherms. Physiosorption mode was involved in the corrosion protection. Electrochemical results revealed an corrosion resistance of copper increases on increasing the inhibitor concentration. The DEIS results indicated that copper corrosion mechanism could be hindered by 50% even after interval of 24 h by optimum concentration of sodium nitrite. The maximum inhibition was achieved with 2000 ppm of NaNO2. With this concentration, inhibition efficiency of up to 61.8% was achievable.
