Investigating metal-inhibitor interaction with EQCM and SVET: 3-amino-1,2,4- triazole on Au, Cu and Au-Cu galvanic coupling J. A. Ramírez-Cano, L. Veleva, R.M. Souto and B. M. Fernández-Pérez 1. Introduction Copper and its alloys are present in almost every aspect of modern life; they are employed extensively in industry ranging from building components to microelectronic applications [1]. Copper is a relatively resilient metal to corrosion in neutral environments and in the absence of chlorides and SO 2 , protected by the formation of a corrosion product (Cu 2 O), known as patina. However, it is susceptible to corrosion in aggressive media, when the patina is converted to other corrosion products [2]. There are several methods to prevent the metallic corrosion and one of them is the use of inhibitors (either organic or inorganic). Organic inhibitors are compounds that applied in very small concentrations are capable of effectively reduce the corrosion rate [3]. Among these compounds those belonging to the group of azoles, which contain nitrogen and/or sulphur, are considered to be effective corrosion inhibitors for copper in a wide range of aggressive environments [4-8]. Inhibitor selection is often based on the gravimetric determination of metal dissolution rate (i.e., mass loss). However, this method provides very little information about the complex interactions between the metal, the inhibitor and the corrosive media. So, in order to optimize inhibition, the involved mechanism in such interactions must be known. This demands the use of electrochemical techniques and surface analysis in the corrosion laboratory. Most of the actual knowledge of the inhibition process of corrosion has been obtained through the use of conventional electrochemical methods such as cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy (EIS) [9]. The development of in-situ scanning probe techniques has allowed the surface characterization with micrometric scale resolution or even smaller. The combination of