Inhibitive Assessment of N-(8-bromo-3H-phenoxazin-3-ylidene)-N,N’-Dimethylaminium, as a Novel Corrosion Inhibitor for Mild Steel in 1.0 M HCl

Subject Areas : Corrosion and protection of materials

Mansoor  Bozorg ¹ (Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran, Iran.)
Taghi  Shahrabi Farahani ² (Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran, Iran.)
Ghodsi  Mohammadi Ziarani ³ (Department of Chemistry, Alzahra University, Tehran, Iran.)
Jaber  Neshati ⁴ (Research Institute of Petroleum Industry, RIPI, Tehran, Iran.)
Zahra  Chaghazardi ⁵ (Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran, Iran.)
Parisa  Gholamzadeh ⁶ (Department of Chemistry, Alzahra University, Tehran, Iran.)
Fatemeh  Ektefa ⁷ (Department of Chemistry, Faculty of Science, Tarbiat Modares University, Tehran, Iran.)

Received: 2014-04-19 Accepted : 2014-05-21 Published : 2014-08-01

Keywords: corrosion, EIS, Inhibitor, Mild steel, DPhDMA,

Abstract :

The inhibition effect of N-(8-bromo-3H-phenoxazin-3-ylidene)-N,N’-dimethylaminium (DPhDMA) on the corrosion behavior of mild steel in 1.0 M HCl solution has been studied. Weight loss measurements, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and quantum chemical calculations were used in this study. Electrochemical results revealed that DPhDMA is an effective mixed type inhibitor for mild steel in 1.0 M HCl solution, and its inhibition efficiency increased with increasing its concentration and with the immersion time of the samples in the corrosive media. The adsorption of DPhDMA also led to a reduction in electric double layer capacitance and an increase in charge transfer resistance confirming its inhibitive effect on the corrosion behavior of mild steel samples. The thermodynamic parameters governing the adsorption process showed that DPhDMA was adsorbed spontaneously on mild steel surface through a combination of physical and chemical mechanisms following Langmuir adsorption isotherm. Quantum chemical calculations were used to correlate the performance of DPhDMA with its electronic structural parameters.