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The paper deals with the synthesis of Guar gum and ethyl acrylate (GG-EEA) composite. The synthesized natural polysaccharide composite was used as a corrosion inhibitor to reduce hydrogen evolution and P110 steel corrosion protection in 15% HCl (Hydrochloric acid). The primary corrosion techniques like weight loss, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) was used to analyze the corrosion inhibition process. The PDP proposed that GG-EEA composite is a mixed-type corrosion inhibitor and inhibits corrosion by blocking the active sites presenting over the metal surface. The corrosion inhibition performance of GG alone is 77.5%, and that of GG-EEA is 92.3% at 500 mg/L. The adsorption of GG-EEA onto P110 steel is spontaneous and mixed type, i.e., both physical and chemical. The conformation of GG-EEA molecule adsorption was done using a scanning electron microscope (SEM), Energy dispersive x-ray spectroscopy (EDX), Atomic force microscopy (AFM), and X-ray photoelectron spectroscopy studies. Density functional theory (DFT) analysis was done to explore the active sites over the inhibitor in metal-inhibitor interaction. Molecular dynamic simulation (MD) simulations study reveals that GG-EEA has more adsorption capacity than GG alone.

Elektrokimyasal büyütme metodu, homojen ince filmlerinoluşumunun mümkün olması, düşük maliyeti, nano-yapıların elde edilebilirliğininkolaylığı, büyük yüzey alanlı büyütmelerin gerçekleştirilebilirliği vestokiyometrideki kontrolü gibi avantajlara sahip olması nedeniyle yaygın birşekilde kullanılmaktadır. Bu çalışmada, nano-yapılı çinko oksit (ZnO) incefilmler elektrokimyasal büyütme metodu kullanarak indiyum tin oksit (ITO) kaplıcam altlıklar üzerine büyütülmüştür. Filmlerin kalitesi üzerine katodikpotansiyel, zaman, sıcaklık ve pH etkileri analiz edilmiştir. ZnO ince filmler dimetilsülfoksit’te (DMSO) 130 °C sıcaklıkta 3600 snbüyütme süresinde -1.0 V katodik potansiyelde elde edilmiştir. X-ışını kırınımı(XRD) analizi, ZnO ince filmlerin açıkça (0002) tercihi yöneliminde tek kristalözelliğe sahip olduğunu doğrulamaktadır. Soğurma ölçümlerine göre, ZnO filmininoptik band aralığı (Eg) 3.4 eV olarak hesaplanmıştır. ITO altlık üzerineelektrodepozisyon yapılan ZnO ince filmlerin korozyon özelliklerielektrokimyasal empedans spektroskopisi (EIS) ve Tafel ölçümleriyleincelenmiştir. Nyquist, açık devre potansiyeli (OCV) ve Bode analizi ZnO’nunyapısal değişimini ve korozyon davranışını anlamak için oluştutulmuş ve Nyquisteğrisine fit yapılarak elde edilen çözelti direnci (Rs), polarizasyon direnci(Rp), sabit faz elementi (CPEdl) ve sabit faz elementi üstel değeri(n) sırasıyla 49.61 Ω, 4.97x10-6 Ω, 6.75x10-6 Ω-1.s.cm-2 ve 0.940 olarak hesaplanmıştır. Tafel eğrisine fityapılarak elde edilen korozyon potansiyeli (Ekor) ve korozyon akımı(Ikor) sırasıyla -0.199 V ve 2.97x10-8 A olarak eldeedilmiştir. Tüm ölçümler dikkate alındığında, büyük korozyon direncininnedeninin büyütme sırasında oluşan kusurların artışına bağlı olarak yüzeypasivasyonuyla açıklanabilir., Electrochemical deposition method (ECD) has been widely used due to itsadvantages in stoichiometry control, large area growth, easy to formnano-structures, being low coast, possible formation of homogeneous thin films.In this study, nanostructured zinc oxide (ZnO) thin films were deposited onIndium tin oxide (ITO)-coated glass substrate using ECD. The effects ofcathodic potential, time, temperature and pH on quality of the films wereexamined. ZnO thin films were achieved with in cathodic potential with -1.0 Vand deposition time with 3600 seconds at temperature 130°C in dimethylsulfoxide (DMSO). X-ray diffraction (XRD) analysis confirmed clearly that theZnOthin films have sinle crystalline properties with a strongc-axis (0002) preferential orientation. According to the absorptionmeasurements, the optical bandgap of the ZnOfilm was calculated asEg 3.4 eV. ZnO thin films electrodeposited on ITO substrate were studied withElectrochemical Impedance Spectroscopy (EIS) and Tafel measurements. Nyquist,open circuit potential and Bode analysis were evaluated to find out thestructural changing of ZnOand its corrosion behavior. With the helpof these plots, solution resistance (Rs), polarization resistance (Rp), aconstant phase element (CPE) and a CPE exponent (n) were calculated as 49.61 Ω,4.97x106 Ω, 6.75x10-6 Ω-1.s.cm-2,0.940, respectively. Also, we examined the ZnO thin films corrosion featureswith the help of tafel measurements. Considering all these measurement, the possiblereason of increasing corrosion resistance can be interpreted as surfacepassivation depending on increasing defects caused by deposition.

Balun Kayan, Didem (Aksaray, Yazar), The electrochemical impedance spectroscopy (EIS) responses of a polypyrrole (PPy)-coated platinum electrode were investigated during N2 -reduction to ammonia in aqueous medium. Kinetic parameters such as film resistance, pore resistance, and double layer capacitance were analyzed as a function of applied potential and polymer film thickness. The relation between kinetic parameters was discussed by combining electrolysis results. It was found that the optimum film thickness of polypyrrole was 0.73 µm and optimum potential for ammonia synthesis was –0.150 V under 60 bar N2 -pressure. The impedance responses under these conditions presented the lowest pore resistance value of ca. 2 Ω cm2 . The electrolyte resistance was also 2 Ω cm2 and the film resistance was ca. 5 Ω cm2 . Tafel slopes calculated from the Tafel curve and EIS-Tafel diagram gave corresponding results: 0.121 V dec −1 and 0.128 V dec −1 , respectively; α-transfer coefficient of 0.49 and an exchange current density with a value of 3.17 10 −3 A cm −2 were characteristic for Had formation in acidic aqueous medium.