The oxidation of the PbS(001) surface with O2 and air studied with photoelectron spectroscopy and ab initio modeling

The chemistry of the PbS(001) surface and especially its oxidation behavior is an important issue both in technology and the environment studies. In the present paper the oxidation behavior has been studied by means of photoelectron spectroscopy using the synchrotron radiation facility BESSY II and a hybrid DFT B3LYP quantum modeling. Based on the calculations, the spectral features observed subsequent to oxidation can be related to the attachment of one to four oxygen atoms to one sulfur atom. The results suggest that the oxidation proceeds via dissociation of the O2 molecules and identifies –SO4 fragments as the final oxidation product. The present combined experimental and theoretical approach to surface reactions is also well suited to the study a number of different solid–gas reactions.