Corrosion control: general discussion

Abstract

Gregory Hunt opened a general discussion of the papers by Anton Kokalj, Angelos Michaelides, and Christopher Taylor: Can you comment on how you apply DFT to non-aqueous systems (hydrocarbons)? How does the non-aqueous system inuence the surface corrosion mechanism?Angelos Michaelides answered: The application of a solvent to DFT can be done by co-adsorbing a very thin lm of e.g. hydrocarbons on top of the slab and running molecular dynamics simulations. This is the so-called ab initio molecular dynamics approach. 1 We have carried out many ab initio molecular dynamics studies of solid-liquid interfaces, e.g. ref. 2 and ref. 3. Although these two papers cited deal with water/solid interfaces, the same approach can in principle be applied to liquid hydrocarbon/solid interfaces. The main and very important drawback with these approaches is their enormous computational cost and if we were to consider the solvent we wouldn't have been able to perform such an extensive set of simulations of different adsorption structures as we have shown in our paper. For complex systems like the one considered here it is probably more appropriate to study a hydrocarbon solvent with a classical method, since good parameterised force elds exist for hydrocarbon molecules. responded: Technically the treatment of aqueous or nonaqueous solvents is similar. This implies that non-aqueous systems can be and have been studied using DFT methods. However, I have no experience with nonaqueous systems, hence I cannot comment on your second question.This journal is

The Importance of Being Inconsistent

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XPS and ToF-SIMS Investigation of Native Oxides and Passive Films Formed on Nickel Alloys Containing Chromium and Molybdenum

“…4,9,[11][12][13][14][15] The exact role of Mo addition in the alloys is still debated. Literature reports that Mo could have a beneficial barrier effect preventing metal dissolution, [16][17][18][19][20][21][22][23] or/and could play the role of (re)passivation promoter. 22,23 Hence, binary Ni-Cr or ternary Ni-Cr-Mo alloys exhibit a stable "passive" state in various solutions.…”

Corrosion control of mild steel in 0.1 M H2SO4solution by benzimidazole and its derivatives: an experimental and theoretical study

“…However, the corrosion of steel usually results in huge nancial losses and many potential safety issues, and anticorrosion technology has aroused the great interest of researchers. [1][2][3] Due to their economy and convenience, chemical inhibitors play an important role in protection and retarding corrosion. [4][5][6] It is generally accepted that inhibitors act via their functional groups adsorbing on the metal surface, which contain either lone pair-donating heteroatoms (N, O, S) or p-bonds, changing the corrosion resistance properties of the metal.…”