Abstract
We present a first principles thermodynamic study of O ad-atom and vacancy formation on the AO- and BO2-terminated (001) surfaces of the PbTiO3 (PTO) and LaMnO3 (LMO) cubic perovskites Our results show that, owing to the highly energetically unfavorable nature of O vacancy formation on these surfaces, O vacancies appear only at high temperatures and practically irrelevant low pressures on the (T, p) surface phase diagram. In contrast, effortless formation of O ad-atoms on the surfaces is encountered at practically achievable pressures and temperatures. Above room temperature and close to atmospheric pressures, we predict clean PbO and TiO2-terminated (001) PTO surfaces as the stable surface phases while partially or fully O ad-atom covered surfaces are found to be more stable for LMO. These results are consistent with the observation that LMO is far more active towards oxidation catalysis than PTO.
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References
- 1.
Properties and Applications of Perovskite Type Oxides, ed. L. J. Tejuca and J. L. G. Fierro (Marcel Dekker: New York, 1993).
- 2.
M. A. Pena and J. L. G. Fierro, Chem. Rev. 101, 1981 (2001).
- 3.
G. Kresse and J. Furthmuller, Phys. Rev. B 54, 11169 (1996).
- 4.
P. E. Blochl, Phys. Rev. B 50, 17953 (1994).
- 5.
R. Martin, Electronic Structure: Basic Theory and Practical Methods (Cambridge University Press, New York, 2004).
- 6.
G. Pilania and R. Ramprasad, Surf. Sci. 604, 1889 (2010).
- 7.
B.G. Shirane and R. Repinsky, Acta Cryst. 9, 131 (1956).
- 8.
J. Rodryguez-Carvajal, M. Hennion, F. Moussa and A. H. Moudden, Phys. Rev. B 57, R3190 (1998).
- 9.
K. Reuter and M. Scheffler, Phys. Rev. B 65, 035406 (2002).
- 10.
K. Reuter and M. Scheffler, Phys. Rev. B 68, 045407 (2003).
- 11.
J. Rogal, K. Reuter, and M. Scheffler, Phys. Rev. B 75, 205433 (2007).
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Pilania, G., Ramprasad, R. Thermodynamics of Oxygen Chemistry on PbTiO3 and LaMnO3 (001) Surfaces. MRS Online Proceedings Library 1309, 1013090323 (2011). https://doi.org/10.1557/opl.2011.731
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