Electrochemical and Quantum Chemical Study of Dibenzylsulfoxide Adsorption on Iron

Abstract

Electrochemical techniques (potentiodynamic polarization curves and electrochemical impedance spectroscoy (EIS) were used to study the effect of dibenzylsulfoxide adsorption on the dissolution of iron in 5% hydrochloric acid. To discuss different proposed mechanisms of dibenzylsulfoxide adsorption at the iron surface a quantum chemical topological method was used, which is suitable for studying the interaction of organic molecules with metal surfaces. Based on the results of the topological modeling, adsorption followed by reduction of dibenzylsulfoxide to sulfide is most favorable. EIS shows the possible effect dibenzylsulfoxide has on the electrochemical desorption of adsorbed hydrogen. Topological studies indicate strengthening of the bond of the adsorbed hydrogen to the metal due to adsorption of the inhibitor.

Electrochemistry and XPS study of an imidazoline as corrosion inhibitor of mild steel in an acidic environment

“…In the case of imidazolines, chemical interaction with metal surface is via the two nitrogen atoms and the plane geometry of the heterocyclic ring [10,11]. Studies report that the adsorption of these organic compounds depends mainly on some physico-chemical properties of the molecule, which are related to its functional group, steric effects, and electronic density of donor atoms [10][11][12].…”

Acetylenic alcohols as inhibitors of iron acid corrosion. Improvement of the inhibition efficiency of a class of substances based on their action mechanism

“…The efficiency of these substances is related to the formation of an insoluble, hydrophobic, thick polymeric film, which lacks the original C≡C triple bond [6][7][8]. The mechanism of film formation, studied in detail in the case of ethynylcyclohexanol [9], 1-octyn-3-ol [10][11][12], 3-phenyl-2-propyn-1-ol [13], propargyl alcohol [14][15][16] generally involves the following consecutive steps: (i) inhibitor chemisorption onto the metal surface through π electrons of the triple bond, (ii) triple bond hydrogenation by atomic hydrogen evolving during the cathodic process, (iii) dehydration (of the alcoholic function), with consequent reactive diene formation and, finally, (iv) polymerisation, reticulation. Detailed studies of chemisorption of alkynols using electrochemical and ellipsometric techniques [17][18][19][20] have established that the octynol molecule lies flat at low additive concentrations and short immersion times, or perpendicular at high concentrations and long contact times.…”

Inhibiting properties and adsorption of some thioamides on mild steel in sulphuric acid solutions

“…The inhibition of corrosion by organic compounds is usually related to their adsorption on the metal surface [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. The adsorption process depends on different factors such as the nature and the charge of the metal surface, the temperature and pH of the corrosion media and the molecular structure of the organic compounds (type of functional groups, steric factor and the electron density distribution).…”

“…For numerous series of organic compounds molecular orbital calculations have been used to correlate structural and electronic parameters of the inhibitor molecules with their adsorption behaviour and therefore with the inhibition efficiency [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29].…”