关键词: Sb, Au(111), Au(100), 不可逆吸附, 欠电位沉积, 扫描隧道显微镜

Abstract: We compare the behaviors of irreversible adsorption of Sb(III) and its reduction, underpotential deposition of Sbon Au(111) and Au(100) as well as mutual interactions of the processes. Based on in-situ scanning tunneling microscopic and cyclic voltammetric results, the substrate structure not only influence anion adsorptionbehavior and thus the Sb adsorption structure, but also the stability of its own structure. On Au(111) surface,the irreversibly adsorbed dense and disordered SbO~(+ )film structure remains after reduction of the film; while on Au(100)surface, due to the coadsorption of SO_4~(2-),an ordered(2×2)structure is formed after reduction.UPD of Sb on Au(111)is accompanied by significant surface alloying, which destroys the ordered structure of the Au (111) surface;while on Au(100)surface,the lattice type and lattice constantare in good match with that of the (100)plane of the stable AuSb2 alloy. Therefore the interaction between Au and Sb appears in the form of ordered surface compound, and surface alloying can be avoided during the process of UPD. The results further reflect the sensitivity as well as importance of the substrate structure.