Hanaa Kadhim Al-Mosawi ( Assistant Lecturer )
Faculty of Science - Chemistry
[email protected]
name: Hanaa Kadhim Kazar PhD in physical chemistry Bachelor of Chemistry Sciences(2002) University of Kufa Master of Chemical Sciences in the field of Physical Chemistry(2012), University of Kufa PhD in physical chemistry 2019 :title of master research photocatlytic degradation of aniline blue dye by using different semiconductors. title of doctor research Synthesis of Some Metal Oxides/ Polythiophene Nanocomposites for Anticorrosion and Water Treatment :abstract of thesis The work includes primary study of electrochemical behavior of three different active species Cr(III), Ce(III) and Sn(II) metals ions which have been performed using cyclic voltammetry technique at stainless steel electrode for determination best potential for oxidation of these compounds. Results indicate that Cr(III) and Ce(III) follow electrochemically quasi -reversible oxidation process with transferring of one electron. However, electrochemical behavior of Sn(II) ions showed irreversible redox process with two electron transfer. Amperometry technique used to study nucleation and growth mechanism during electrolytic deposition of thin film on surface of stainless steel electrode by applying sufficient potential ,which giving a three dimension instantaneous nucleation and growth model of Cr2O3 , three dimension progressive nucleation and growth model of CeO2 , a two dimension progressive nucleation and growth model for SnO2 particles and two dimension instantaneous model for polythiophene film synthesis. In this study electropolymerization of thiophene on stainless steel electrode has been investigated using cyclic voltammograms in acid solutions under nitrogen atmosphere at different reaction conditions such as perchloric acid concentration, monomer concentration and temperature. The electropolymerization process follows first‐order kinetics with respect to the monomer concentration , the order of reaction with respect to the supporting electrolyte concentration (HClO4) was found to be 0.9324. The experimentally obtained kinetic equation was Rp = KE [HClO4]0.9324 [monomer] 1.017. The effect of temperature in electropolymerization of thiophene was studied and the apparent activation energy ,enthalpy and entropy were calculated and were equal to 36.3 KJ.mole-1, 33.8 KJ.mole-1 and -197.8 J. mole-1 respectively . Electrosynthesis of three different series of Polythiophene(PT) nanocomposites include PT/ Cr2O3, PT / SnO2 and PT / CeO2 have been investigated . The electrical conductivity was measured for synthesized compounds by using two- point probe technique. The resulted shows that the conductive polymer /metal oxide nanocomposites has higher conductivity than semiconductor. All synthesis compounds were characterized by x-ray diffraction (XRD), FTIR ,Raman analysis , Thermal gravity analysis (TGA) , UV-Visible analysis , Atomic force microscopy (AFM), Field emission Scanning electron microscopy (FESEM) , energy-dispersive X-ray (EDX) spectroscopy and Transmission electron microscopy (TEM). The average size of crystalline, the size of crystals of Cr2O3 ,SnO2 , CeO2 , polythiophene , PT/ Cr2O3 ,PT/ SnO2 and PT/ CeO2 prepared were calculated by using the Scherrer equation. The results display that the average size of the c for all compounds are: (41.4, 14.6,23.35 , 24.34, 32, 17and31.78) nm according to XRD and (60.88, 67.99,81.85 , 45.79, 75.25, 87.2and 93.18) nm according to AFM and (46,95, 68, 59.7, 55, 42, and 41)nm according to FESEM techniques, respectively. Electrocatalytic activity of PT , Cr2O3, SnO2 , CeO2 , PT/ SnO2, PT/ Cr2O3, and PT/ CeO2 anodes was investigated by electrochemical degradation of Reactive blue 4 dye in presence of sodium chloride as an electrolyte to investigate the effect of nanocomposites coating. The color removal efficiencies were 41%, 37 %, 32 %, 28 %, 54% , 62% and 91 % respectively for above anodes, at the end of 15 minutes of electrolysis at potential of 3 V. The anticorrosion activity of (PT , Cr2O3, SnO2 , CeO2 , PT/ Cr2O3, PT/ SnO2, and PT/ CeO2 ) was studied by the weight loss and Potentiodynamic polarization test at different concentration of inhibitors , different immersion time and different temperature . The weight loss of stainless steel was reduced after coated by the inhibitor . The corrosion rate (CR) is decreased, and the inhibition efficiencies (IE%) is increased with the increase of the studied inhibitor concentration. Polarization curves show that the substrate coated with composite film has a lower corrosion current density and a more positive corrosion potential value than Metal oxides coated samples.