The electrochemical synthesis of poly(pyrrole-co-o-anisidine) on 3102 aluminum alloy and its corrosion protection properties

The electrochemical syntheses of polypyrrole (PPy) and poly(pyrrole-co-o- anisidine) were achieved on 3102 aluminum alloy (Al) from 0.1 M monomer (pyrrole:o-anisidine, 8:2) containing 0.4 M oxalic acid solution using the cyclic voltammetry technique. The synthesized films were characterized by FT-IR spectroscopy. The thermal stability of films was determined by thermogravimetric analysis (TGA) technique. Surface morphologies were characterized by scanning electron microscope (SEM) images. The potential of zero charge (pzc) of Al was determined using electrochemical impedance spectroscopy (EIS). The corrosion behavior of samples was investigated with open circuit potential (E ocp)-time, EIS, and anodic polarization techniques. It was found that copolymer coated Al provides better barrier property against of corrosion in 3.5% NaCl solution. © 2010 Elsevier B.V. All rights reserved

Visible light photocatalysis of ni-deposited TiO2 nanotubes for methyl orange degradation in alkaline medium

The photocatalysis of TiO2 nanotubes (Ti/TNT) and Ni-deposited TiO2 nanotubes (Ti/TNT-Ni) for methyl orange degradation was investigated. Methyl orange was selected as the model pollutant, and its photocatalytic degradation was determined in 1 mol/L KOH solution. Ti/TNT was produced by anodizing method, and the electrodeposition of nickel on TNT was performed galvanostatically. The characterization of electrodes was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction analysis. The electrochemical behavior of the electrodes was determined by cyclic voltammetry and electrochemical impedance spectroscopy. The irradiation was applied by visible light source (k = 635 nm) for 48 h. UV/vis spectroscopy was used for determination of the concentration of methyl orange. Furthermore, after 48-h irradiation, the solutions were analyzed by Fourier transform infrared spectroscopy. Results showed that the concentration of methyl orange decreased from 100 ppm (10-6) to 16 ppm, after 48-h irradiation with the photocatalysis of Ti/TNT-Ni

Experimental and theoretical studies on electrochemical synthesis of poly(3-amino-1,2,4-triazole)

The electrochemical synthesis of poly(3-amino-1,2,4-triazole) (PATA) on the platinum (Pt) electrode was achieved in ammonium oxalate solution by cyclic voltammetry technique. The conductivity of film was measured with four probe technique, the surface morphology was monitored with atomic force microscopy (AFM) and characterization was achieved by Fourier transform infrared spectroscopy (FT-IR) and UV-vis spectroscopy techniques. The thermal stability of polymer has also been investigated by the means of thermogravimetric analysis (TGA). The electrochemical stability of Pt/PATA was investigated in different buffer solutions. The quantum theoretical calculations employed and some parameters (dipole moment, E HOMO , E LUMO ) were determined. © 2012 Elsevier B.V

The photoelectrocatalytic activity, long term stability and corrosion performance of NiMo deposited titanium oxide nano-tubes for hydrogen production in alkaline medium

In this study, titanium oxide nano-tubes are doped with Ni and Mo particles with various chemical compositions, in order to put forth the efficiency of single and binary coatings on hydrogen evolution reaction (HER) in 1 M KOH. The characterization was achieved by cyclic voltammetry, scanning electron microscopy and energy dispersive X-ray analysis. The water wettability characteristics of electrode surfaces were investigated using contact angle. The long-term catalyst stability and corrosion performance were determined by current–potential curves and electrochemical impedance spectroscopy. Furthermore, photoelectrochemical behavior was determined via linear sweep voltammetry. Results showed that, nano-structured Ni and Mo deposited titanium oxide nano-tubes decrease the hydrogen over potential and increase HER efficiency, it is stable over 168 h electrolysis and it exhibits higher corrosion performance. © 2017 Elsevier B.V

The role of Spirulina platensis on corrosion behavior of carbon steel

The corrosion behavior of carbon steel (CS) was investigated in 3.5% NaCl solution in the presence and absence of Spirulina platensis (SP) bacteria. For this purpose, the weight loss measurements, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization techniques were used. The counts of SP were monitored with UV-VIS spectrophotometer, optical microscope and the dissolved oxygen (DO) was determined in all solutions. The morphology of the electrodes surfaces were characterized with SEM images. The results show that, SP decreased the corrosion rate and the current density values of CS; the corrosion potential was shifted to nobler values, the polarization resistance values were increased. All parameters reveal that the SP effectively protected CS against corrosion and reduced its corrosion rate in 3.5% NaCl solution. © 2011 Elsevier B.V. All rights reserved.The authors are greatly thankful to Cukurova University Research Fund and The Scientific and Technical Research Council of Turkey (TUBITAK) for financial support

Experimental and theoretical investigation of 3-amino-1,2,4-triazole-5-thiol as a corrosion inhibitor for carbon steel in HCl medium

The inhibition effect of 3-amino-1,2,4-triazole-5-thiol (3ATA5T) was investigated in 0.5. M HCl on carbon steel (CS) by electrochemical impedance spectroscopy and potentiodynamic measurements at various concentrations and temperatures. Results showed that the correlation between experimental (inhibition efficiencies, ?. Gads, Ea) and quantum calculation parameters (dipole moment, EHOMO, ELUMO). The high inhibition efficiency was declined in terms of strongly adsorption of protonated inhibitor molecules on the metal surface and forming a protective film. © 2011 Elsevier Ltd.This study has been financially supported by the Cukurova University research fund . The authors are greatly thankful to Çukurova University Research fund . The authors also thank to The Scientific and Technical Research Council of Turkey (TUBITAK)

Electrochemical synthesis of novel conductive polymer and corrosion protection properties on aluminium

In this study, the new original copolymer film of pyrrole and 2-amino-4-methyl-pyridine has been electrochemically synthesised on 7075 aluminium alloy. The synthesis was achieved in aqueous oxalic acid containing 1 : 1 monomer feed ratio. The characteristics of copolymer film were compared with polypyrrole film on Al under the same conditions. The characterisation of synthesised polymers was realised with the help of scanning electron microscopy. Fourier transform infrared spectroscopy and gel permeation chromatography techniques. The conductivity values of films were measured with four-probe technique. The stability of copolymer film as a coating material has also been investigated in 35% NaCl solution. The quantum theoretical calculations have been employed, and some parameters (dipole moment, energy of the highest occupied molecular orbital and lowest unoccupied molecular orbital) were determined. The calculated quantum parameters revealed correlation with experimental data. Under such severe conditions, the copolymer film exhibits protective coating behaviour on Al. This original, highly stable and conductive copolymer film can find wide application area for various purposes (anticorrosive, electrocatalytic, etc.). © 2013 Institute of Materials, Minerals and Mining

Polyindole top coat on TiO2 sol-gel films for corrosion protection of steel

The protection efficiency of polyindole film on stainless steel was enhanced via titanium dioxide pre-coating. The characterization of coatings was achieved by nuclear magnetic resonance and Fourier-transform infrared spectra. The surface morphology of electrodes was monitored with scanning electron microscope. The corrosion performance was investigated in 3.5% NaCl solution by electrochemical impedance spectroscopy and potentiodynamic measurements. The quantum calculations were employed, and theoretical parameters were determined. Results showed that the correlation between experimental and theoretical parameters. The high protection efficiency was observed against corrosion on the steel surface via forming a protective polyindole top coated titanium dioxide film. © 2012 Elsevier Ltd.This study has been financially supported by the Cukurova University research fund . The authors are greatly thankful to Çukurova University Research fund. The authors also thank to The Scientific and Technical Research Council of Turkey (TUBITAK)

Copper/polypyrrole multilayer coating for 7075 aluminum alloy protection

The corrosion behavior of 7075 aluminum (Al), copper modified Al (Al/Cu), polypyrrole modified Al (Al/PPy) and copper (under layer)/polypyrrole (top layer) modified Al (Al/Cu/PPy) samples were investigated in 3.5% NaCl solution. The copper plating on aluminum was carried out from acidic copper sulphate solution by electroless method. Polypyrrole (PPy) was electrochemically synthesized on Al and Al/Cu electrodes from 0.1 M pyrrole containing 0.4 M oxalic acid solution using cyclic voltammetry technique. The films synthesized were characterized by Fourier transform infrared spectroscopy (FT-IR). The thermal stability of PPy films was investigated by thermogravimetric analysis (TGA). The surface morphologies were examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The corrosion behavior of samples was investigated by electrochemical impedance spectroscopy (EIS) and anodic polarization curves. The data obtained showed that the synthesis of PPy on top of the Cu layer significantly enhances the corrosion resistance of Al by exhibiting a barrier effect against the attack of corrosive environment. © 2011 Elsevier B.V. All rights reserved

Inhibition effect of 2-amino-4-methylpyridine on mild steel corrosion: Experimental and theoretical investigation

The effect of 2-amino-4-methylpyridine (AMP) on the corrosion behavior of mild steel (MS) in 0.5. M HCl is investigated with electrochemical methods and theoretical calculations. The electrochemical tests show that the polarization resistance of MS increasing the presence of AMP in acid solution. Adsorption of AMP on MS surface is a physical and obeys the Langmuir isotherm. The quantum parameters signaled adsorption occurs on amine and methyl substituents of AMP. The inhibition efficiency is related to frontier orbital's energy band gap of AMP, which are 5.357 and 6.490. eV for neutral and protonated molecules in aqueous solution, respectively. © 2014 Elsevier Ltd