In situ STM study of zinc electrodeposition on Au(111) from the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethylsulfonate

The electrodeposition of Zn on Au(111) was investigated with cyclic voltammetry (CV) and in situ scanning tunneling microscopy (STM) in the air and water stable ionic liquid 1-ethyl-3-methylimidazolium trifluoromethylsulfonate ([EMIm]TfO) with a Zn(TfO)(2) concentration of 0.2 M. It has been found that the structure [EMIm]TfO/Au(111) is very complex. Furthermore, the addition of Zn(TfO)(2) changes the interfacial structure significantly. The first STM-probed Zn islands appear at +0.3 V, and their growth leads to the formation of a thin zinc layer. A bulk deposition of Zn is obtained with in situ STM at -0.1 V. Furthermore, in situ STM reveals that the deposition of Zn is accompanied by the formation of Au-Zn surface alloys.