A comprehensive study about anti-corrosion behaviour of pyrazine carbohydrazide: Gravimetric, electrochemical, surface and theoretical study

A relative investigation of various synthesized hydrazone derivatives was examined for their inhibitive impact on mild steel in 1 M HCl medium, using the measurements of weight loss and electrochemical procedures. The different parameters, for example, corrosion rate, inhibition efficiency, and surface coverage were estimated. The weight loss strategy demonstrates the rise in the inhibition efficiency on expanding the amount of inhibitor. The inhibition activity of the compounds was expected to happen by means of adsorption over the steel surface which abides the Langmuir isotherm model. The inhibitors are predicted to be mixed inhibitors i.e. influencing both cathodic hydrogen evolvement and anodic metal dissolution. The surface investigation strategies (SEM-EDX, AFM, and XPS) further validated that the corrosion hindrance happens because of the adsorption of the inhibitors over the metal/solution interface. Also, the outcomes of the theoretical approach supported all the experimental results by illustrating the similar trend of inhibition efficiencies of various hydrazones. (C) 2019 Elsevier B.V. All rights reserved.