DFT study of methanol adsorption on PtCo(111)

• Published in: Applied surface science Vol. 420; pp. 383 - 389
• Main Authors: Orazi, V., Bechthold, P., Jasen, P.V., Faccio, R., Pronsato, M.E., González, E.A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 31-10-2017
• Subjects: Adsorption; Bonding; DFT; Methanol; PtCo; DFT; Adsorption; Bonding; PtCo; Methanol
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2017.05.159

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•Methanol is adsorbed on a FCT PtCo surface on top of Co atom with an OCo distance of 2.24Å.•COCo angle is 142° and the COH angle is about 111°.•The CO and OH bonds show a small elongation whereas the CH bonds are shortened.•The charge transfer seems to occur from C atom to O atom, and then to the Co1 atom (surface).•The CoO calculated frequency is 250cm−1, which is similar to the experimentally reported.
Methanol adsorption on PtCo(111) surface at low coverage is studied using Density Functional Theory (DFT) calculations without and with van der Waals corrections. We investigated the PtCo FCT alloy surface with a uniform distribution. The most favorable site for CH3OH adsorption is on top of a Co atom, with an adsorption energy of −0.92eV. Methanol attachs to the surface by the O atom, with a distance of 2.24Å. The molecule presents a small distortion after adsorption. The COCo bond angle is 142°. The CH bonds are strengthened whereas the CO and OH bonds are weakened. A charge transfer from C atom to O atom occurs upon adsorption, and then further transfer occurs to the Co atom on the surface. The calculated vibrational frequencies for adsorbed methanol present a red-shift displacement compared to gas-phase, confirming the adsorption process.