A periodic DFT study of water and ammonia adsorption on anatase TiO2 (001) slab

Date

2010-06-15

Author

Erdogan, Rezan
Ozbek, Olus
Önal, Işık

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Water and ammonia adsorption mechanisms on anatase TiO2 (001) slab surface are investigated by means of periodic DFT approach. Molecular and dissociative adsorption energies for water are calculated to be -15 kcal/mol and -32 kcal/mol, respectively. Similarly, molecular and dissociative adsorption energies of ammonia on the same surface are found as 25 kcal/mol and 20 kcal/mol. A reverse result in this order is reached for the previous case of ONIOM cluster study (23 kcal/mol and 37 kcal/mol, respectively). The vibration frequency values are computed for the optimized geometries of adsorbed water and ammonia molecules on anatase TiO2 (001) slab surface and compared with the values reported in the literature.

Subject Keywords

Ammonia adsorption, Water, Anatase, DFT

URI

https://hdl.handle.net/11511/30771

Journal

SURFACE SCIENCE

DOI

https://doi.org/10.1016/j.susc.2010.03.016

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

R. Erdogan, O. Ozbek, and I. Önal, “A periodic DFT study of water and ammonia adsorption on anatase TiO2 (001) slab,” SURFACE SCIENCE, pp. 1029–1033, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30771.