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Calculation of the adsorption of CO on Platinum (111) surface via Density Functional Theory#

We introduce Density Functional Theory (DFT) calculation for the adsorption of CO on Platinum (Pt) (111) surface with Advance/NanoLabo, an integrated GUI for nanomaterials.

The entire process from modeling to running calculation and analysis of results was executed on Advance/NanoLabo.

Calculation of single-crystal Pt#

Firstly, we performed structural optimization of bulk single-crystal Pt.

Consequently, we obtained the relaxed structure with a lattice constant of 4.02 Å.

The lattice constant of bulk single-crystal Pt reported experimentally is 3.92 Å1 and relative error between experimental value and calculated value is 2.5 %.

The energy change in structural optimization The optimized bulk structure of Pt
The energy change in structural optimization
The optimized bulk structure of Pt

Calculation of Pt (111) surface#

Secondly, we generated the four-layer slab model of Pt (111) from the optimized bulk structure of Pt.

By introducing thick vacuum layer in the surface normal direction, we calculated Pt (111) surface under three-dimensional periodic boundary condition.

We fixed the lower two layers in structural optimization of the slab model.

Setting of the Miller indices of exposed surface
The generation of slab model (Pt (111))
The setting screen of fixed atoms
The optimized structure of the slab model

Calculation of CO/Pt(111)#

Finally, we generated the four-layer slab model of Pt (111) with adsorbed CO at on-top site (Pt (111)/CO) and executed structural optimization of Pt (111)/CO.

Also, we carried out the structural optimization of isolated CO molecule to calculate adsorption energy.

Although there are some adsorption sites on Pt (111) surface besides on-top site, it is known experimentally that CO prefer on-top site to any other sites at low coverage4.

We calculated total energy of Pt (111)/CO, Pt (111) slab model and isolated CO molecule respectively and obtained adsorption energy of 1.45 eV2.

The adsorption energy of CO on on-top site of Pt (111) reported experimentally is 1.39 eV3 and the calculated value is comparable with the experimental value.

The generation of Pt (111)/CO model
The optimized structure of Pt (111)/CO
The isolated CO molecule model

関連ページ#

  1. C. Kittel: "Introduction to Solid State Physics (the eighth edition) first volume and second volume", (Translated by UNO, R., TSUYA, N., Niizeki, K., Morita, A. and Yamashita, J.), Maruzen Publishing (2005) Published in Japanese. ↩

  2. Adsorption energy  ↩

  3. Iwasawa, Y., Nakamura, Z., Fukui, K., Yoshinobu, J.: "Basic Surface Chemistry", Kagaku-Dojin Publishing (2010) Published in Japanese. ↩

  4. P. J. Feibelman, et al: "The CO/Pt(111) puzzle." J. Phys. Chem. B 105.18 (2001) 4018–4025. ↩