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arXiv · 0908.3239

Activated dissociation of O2 on Pb(111) surfaces by Pb adatoms

Yu Yang·Jia Li·Zhirong Liu·Gang Zhou·Jian Wu·Wenhui Duan·Peng Jiang·Jin-Feng Jia·Qi-Kun Xue·Bing-Lin Gu·S. B. Zhang
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Abstract

We investigate the dissociation of O2 on Pb(111) surface using first-principles calculations. It is found that in a practical high-vacuum environment, the adsorption of molecular O2 takes place on clean Pb surfaces only at low temperatures such as 100 K, but the O2 easily desorbs at (elevated) room temperatures. It is further found that the Pb adatoms enhance the molecular adsorption and activate the adsorbed O2 to dissociate during subsequent room-temperature annealing. Our theory explains the observation of a two-step oxidation process on the Pb surfaces by the unique role of Pb adatoms.

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Yu Yang, Jia Li, Zhirong Liu, Gang Zhou, Jian Wu, Wenhui Duan, Peng Jiang, Jin-Feng Jia, Qi-Kun Xue, Bing-Lin Gu, S. B. Zhang. 2009-08-22. Activated dissociation of O2 on Pb(111) surfaces by Pb adatoms. https://doi.org/10.1103/physrevb.80.073406

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