Ab-initio DFT Modeling of Alkanethiols as Carbon Steel Corrosion Inhibitors

탄소강 부식 억제제로서 알칸 티올의 Ab-initio DFT 모델링

In the present work, we simulated and explained the bonding of three alkanethiols - hexanethiol (HT), decanethiol (DT), and 11-mercaptoundecanoic acid (MDA) - with Fe(110) surface and Fe2 clusters using Density Functional Theory (DFT) to probe the corrosion inhibition mechanisms. The interaction energies computed from periodic DFT calculations successfully predicted the experimental inhibition performance. We have found strong covalent bond formation between S(thiol) and Fe-atoms in both approaches, further confirmed by the projected density of states and electron density difference. Besides, natural bond orbital (NBO) charge distribution showed that DT had stronger electron-donation and back-donation synergic interactions with Fe-atoms.